This formula describes how the amount of Francium-223 (N(t)) decays over time (t). The initial amount of Francium-223 is 15 grams, and each 22 minutes the amount is halved.
Step 1: Start with the formula
N(t) = 15 * (1/2)^(t/22).
Step 2: Substitute the value for N(t). For example, if you want to find the amount of Francium-223 after 44 minutes,
N(44) = 15 * (1/2)^(44/22).
Step 3: Calculate the fraction (1/2)^(44/22). This is equal to (1/2)^2, or 1/4.
Step 4: Multiply the initial amount of Francium-223 (15) by the fraction (1/4). The result is
15 * (1/4) = 3.75 grams.
The formula N(t) = 15 * (1/2)^(t/22) describes how the amount of Francium-223 (N(t)) decays over time (t). The initial amount of Francium-223 is 15 grams, and each 22 minutes the amount is halved. To calculate the amount of Francium-223 after a certain time, substitute the value for N(t). Then calculate the fraction (1/2)^(t/22) and multiply it by the initial amount of Francium-223 (15). The result is the amount of Francium-223 after the specified time. For example, after 44 minutes, the amount of Francium-223 is 15 * (1/4) = 3.75 grams.
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The double number line shows that a traffic signal allows traffic through the intersection for 363636 seconds. A double number line with 2 tick marks. The line labeled Time, seconds, reads from left to right: 0, 36. The line labeled Percentage, reads from left to right: 0 percent, 100 percent. A double number line with 2 tick marks. The line labeled Time, seconds, reads from left to right: 0, 36. The line labeled Percentage, reads from left to right: 0 percent, 100 percent. Complete the table to show different percentages of the time the signal allows. Time (\text{s}sstart text, s, end text) Percentage 100\%100%100, percent of 36\,\text{s}36s36, start text, s, end text 25\%25%25, percent of 36\,\text{s}36s36, start text, s, end text 125\%125%125, percent of 36\,\text{s}36s36, start text, s, end text Report a problem
The percentages for this problem are calculated as follows:
100% of 36 seconds: 36 seconds.25% of 36 seconds: 9 seconds.125% of 36 seconds: 45 seconds.How to obtain the percentages?The percentages in this problem are obtained applying proportions, multiplying the total amount by the decimal equivalent of the percentage.
Hence the amount that represents 100% of 36 seconds is obtained as follows:
1 x 36 = 36 seconds.
(as a percentage of 100% has a decimal equivalent of 1).
The amount that represents 25% of 36 seconds is obtained as follows:
0.25 x 36 = 9 seconds.
(as a percentage of 25% has a decimal equivalent of 1).
The percentage of 125% of 36 students can be obtained combining the two previous expressions as follows:
1.25 x 36 = 1 x 36 + 0.25 x 36 = 36 + 9 = 45 seconds.
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The tables show the prices for ordering team jerseys from two different companies. You can use the information to write ratios showing the relationship between the cost and the corresponding number of jerseys.
Company A: 1/5=5 25/5=5 50/10=5 75/15=5.
These ratios are all equivalent
This relationship is proportional.
company B: 5/1=5 20/5=4 40/10=4 69/15=4.
These ratios are not all equivalent.
This relationship is not proportional.
Is the ratio constant or varying for company B? Explain
When we compare two ratios, they are said to be equivalent. To determine whether two or more ratios are equivalent, they can be compared to one another. For instance, the ratios 1:2 and 2:4 are equivalent.
Find the equivalent ratio by what method?Equivalent ratios are two ratios with the same value. By multiplying or dividing the two amounts by the same number, you can determine the equivalent ratio. Finding equivalent fractions follows the same procedure.
A ratio formula is what?The ratio formula can be used to represent a ratio as a fraction. The ratio formula is given as a:b = a/b for any two quantities, let's say a and b.
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How do you do a simple random sample on a calculator?
Using the calculator there are various methods according to the calculator we used and the approach we follow, Basic answer is to select N and generate random number.
What do you mean by random sampling?Random sampling is a method of selecting a sample from a population in such a way that each member of the population has an equal probability of being selected. This ensures that the sample is representative of the population, and reduces bias in the sampling process. In simple random sampling, a random sample is drawn from a larger population by using random number generators, tables of random numbers, or other methods that ensure that each member of the population has an equal chance of being selected.
What are samples?A sample is a portion or a subset of a population that is selected for the purpose of studying characteristics of the population. The sample is used to make inferences or conclusions about the population from which it was drawn. The sample is usually smaller in size than the population, and it is selected through a process called sampling. The process of sampling is used to select a sample that is representative of the population, meaning that the sample has similar characteristics as the population.
Define the population size (N) and the sample size (n) that you want to obtain.
Use the calculator's random number generator to generate a random number between 1 and N. This will be the first element of your sample.
Repeat step 2 to generate the remaining elements of the sample, making sure that each element is different from the previous ones.
Record the elements of the sample, which are the random numbers that have been generated.
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If you deposit $8,000 into an account paying 6% simple interest, how long until there is $13,000 in the account? Round to the nearest
tenth
• The balance of the account will be $13,000, in
years.
After 10 years the balance of the account will be $13000.
What is simple interest?
A simple interest is one that does not compound anyway. In this system, a creditor only pay interest on the initial amount and the rate of interest is not changed during the time period.
How many years needed to reach the required amount?
given, initial deposit money = initial principal amount = $8000
initial money is denoted by P
interest rate (annually), r = 6%
generally, simple interest is annual.
expected amount after t years = final amount = $13000
final amount is denoted by A.
t is the time in years.
According to the formula for simple interest, A = P (1 + rt)
$13000 = $8000(1 + 6/100×t)
$13000/ $8000 = (1 + 0.06t)
(1 + 0.06t) = 1.625
0.06t = 0.625
t = 10.417 years or t = 10 years
Therefore, after 10 years the balance of the account will be $13000.
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Andrew buy 8 pound of apple for $12. 0. He want to know and ue the unit rate of the cot per pound. True or Fale: Two pound of apple cot more than $3. 50
It is false that the cost of two pounds of apple cast is more than $ 3.50.
Finding the cost of a given quantity:Here to find the cost of the given quantity we need to find the cost of 1 unit i.e 1 pound in the given problem so that we can find the cost of given quantities. It is called a unitary method.
Given that
Andrew buy 8 pounds of apples for $ 12.00
Let 'x' be the cost of 1 pound of apples
By the given data,
=> 8x = $ 12
=> x = 12/8
=> x = 1.5
The cost of 1 pound of apples = $ 1.5
Cost of 2 pounds apples = 2 × 1.5 = 3
Therefore,
It is false that the cost of two pounds of apple cast is more than $ 3.50.
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25 less than the sum of a number and 5 results in 15 what is the number
The number is 35.
What is an equation?
An equation is a statement of equality between two expressions. It uses the equal sign (=) to show that the expressions on either side of the sign have the same value.
For example 2x+3=5y-7z, and x+y=5 are examples of equations.
In solving your problem,
25 less than the sum of a number and 5 results in 15, can be written as an equation like this:
let x be the number we want to find.
x + 5 =15+25 (25 less than the sum of x+5)
x + 5 = 40
then
x=40-5
x=35
So the number is 35.
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What are the 3 types of translation?
When the state of an object is changed from one to another it is known as translation in mathematics and they are of three types.
The three types of translation in math are
horizontal translationvertical translationcompression translationWhen the object moves either from left to right or from right to left it is known as vertical translation.
The movement in up or downward direction of the graph is known as horizontal translation.
The domain of the function remains same in both the cases.
A translation in which the size of the object decreases or is compressed is known as the compression translation.
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Condos in Georgetown go up in value by 10% each year. If the Sutton family's condo is now worth $120,000, what will it be worth in 8 years?
With 8 percent increase each year the Sutton family's condo's worth in 8 years will be $216000.
What is exponential function?An exponential function is a mathematical function in the form f(x) = ax, where {x} is a variable and {a} is a constant which is called the base.
Given is that Condos in Georgetown go up in value by 10% each year. Sutton family's condo's current worth is $120,000.
We can write the function to calculate the worth after {T} years as follows.
A{T, R} = A{I} {1 + RT}
A{T, R} = {120000} {1 + (10/100) x 8}
A{T, R} = {120000} {1 + 0.1 x 8}
A{T, R} = {120000} {1 + 0.8}
A{T, R} = {120000 x 1.8}
A{T, R} = 216000
Therefore, the Sutton family's condo's worth in 8 years will be $216000.
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The mighty oak tree outside of Matt's house had to be cut down. He missed the beautiful tree and the shade it provided and wanted to replace it with an oak tree that would grow quickly. The Nuttall Oak (Quercus nuttalli), the fastest-growing oak tree, grows 7 to 8feet per year (we'll assume it grows at a constant rate). At maturity, it can be up to 50 feet tall.
Which of the following equations, where t represents time in years and h represents the height in feet, describe growth that is slower than the Nuttall Oak growth rate?
CHOICES:
A: h=5t
B: h=8.5t
C: h=10t
D: h=50t
Growth that is slower than the Nuttall Oak growth rate is h=5t.
What is equation?An equation is a mathematical statement that expresses two values as being equal. It is the basic building block of algebra and can be used to solve for unknown values, or to show the relationships between two or more values. Equations use mathematical operators such as addition, subtraction, multiplication, and division, as well as symbols and numbers, to express relationships between values. An equation can be written in the form of an expression, a system of equations, or a single equation. In all cases, an equation requires both sides of the equation to be equal in order to be valid and have a solution.
This equation describes growth that is slower than the Nuttall Oak growth rate because it has a lower rate of growth of 5 feet per year. The Nuttall Oak grows 7 to 8 feet per year, so any equation with a growth rate lower than that would be slower. Choices B, C, and D have higher growth rates than the Nuttall Oak, so they would not be slower than the Nuttall Oak growth rate.
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N(t) = 8950 times (0.7)^2t
Answer: t = 0
Step-by-step explanation:
Expand 8950×0.7²: 4385.5t
8950(0.7) ²t
8950×0.49t = 4385.5t
N(t) = 4385.5t
N(t) - 4385.5t=0
Factor N(t) - 4385.5t: t (N - 4385.5)
t (N - 4385.5) =0
t=0
Which of the following statements correctly describes the graph? A. The graph represents a nonlinear function with a constant rate of change. B. The graph represents a nonlinear function with an increasing rate of change. C. The graph represents a linear function with a constant rate of change.
The statement that correctly describes the graph is given as follows:
C. The graph represents a linear function with a constant rate of change.
How to classify the functions as linear or non-linear?A function is classified as linear or non-linear depending on the rate of change of the function.
If the rate of change of the function is constant, that is, when x changes by one amount, y always changes by the same amount, then the function is classified as linear.
Conversely, if the rate of change of the function is different for different intervals, then the function is classified as non-linear.
As the graph presented at the end of the answer shows a linear function with constant slope, it has a constant rate of change, thus it is linear and option c is correct.
Missing InformationThe graph is given by the image presented at the end of the answer.
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Solve for x and express the zeros in a + bi form x^2=6x-10
Solution of the equation is x = 3 ± i that is a complex number where 3 is the real part and i is the imaginary part.
What is quadratic equation?The equation of two-degree polynomial having one variable is called quadratic equation.
The solution of a quadratic equation is either real or complex. We use quadratic equation formula for solution whenever we cannot expand, and factoring a given two-degree polynomial equation.
How to solve the given equation?given equation, x² = 6x -10
x²-6x +10 =0
This equation cannot be expanded so we need to write the formula for quadratic equation to solve it.
we know that standard form of a quadratic equation is given by
ax² + bx +c = 0
where a is the coefficient of x², b is the coefficient of x and c is the constant.
the solution of the equation is given by x = -b ± √ (b² - 4ac) / 2a
Now, the solution for the above equation is x = 6 ± √ (6² - 4×1×10) / 2×1
x = 6 ± √ (36 -40) / 2
x = 6 ± √-4 / 2
as √-4 = √-1 ×2
x = 6 ± 2 √-1 /2
divide both numerator and denominator by 2
x = 3± i as √-1 = i
this is the solution in (a + bi) form a = 3 and b = 1
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The coordinates of 3 of the vertices of a parallelogram are (-3, 4), (-2, 1), and (2, 6). What is the equation for the
line containing the side opposite the side containing the first two vertices? (Remember, opposite sides of a
parallelogram are parallel.)
A.
B.
-2
y=-x
5
2
y=-x+5
52.38
C. y=-3x
D. y=-3x+12.
y = -3x + 12 is the equation for the line containing the side opposite the side containing the first two vertices.
Given coordinates:
(-3,4) ; (-2,1) ; and (2,6)
let us solve for the slope.
Since , parallel sides have the same slope.
m = y2-y1 / x2-x1
m = 1 - 4 / -2-(-3)
m = -3 / 1
m = -3
y = mx + b
Since , (2,6) is a point which passes through the line . Hence , it must satisfy the equation.
Therefore,
6 = -3(2) + b
6 = -6 + b
6 + 6 = b
12 = b
On Substituting , values of m and b in y = mx +b , we get y = -3x +12 which is the required equation of the line.
Hence, y = -3x + 12 is the equation for the line containing the side opposite the side containing the first two vertices.
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You have to pay 25% income tax on all of the money you make. If you made $3000 this month, how much did you have to pay in taxes this month?
Please answer ASAP! :{
You get 20 points! :)
Answer: 750
Step-by-step explanation:
3000/4= 750
750
Can you help me with this
Answer:
y = 3/2x - 3
Step-by-step explanation:
first find slope (m):
m = (-3/2 -(-15/2)) / (1 - (-3)) = (12/2) / 4 = 6/4 = 3/2
plug the point (1, -3/2) into the point-slope form (y-y1) = m(x-x1):
y - (-3/2) = 3/2(x-1)
y + 3/2 = 3/2x -3/2
now put it in slope-intercept form y = mx + b:
y = 3/2x -6/2
y = 3/2x - 3
A pound of strawberries costs $3.28 and a pound of apples costs $4.63. What is the combined cost of 0.7 pound of strawberries and 1.4 pounds of apples
The combined cost of 0.7 pound of strawberries and 1.4 pounds of apples is $8.778.
What is called a pound?The Latin word "poundus," which means "weight," is whence its name originates.
Any of the many weight and mass units. especially: a measurement that is commonly used by English-speaking peoples and equals 16 ounces (about 0.454 kilograms) see measurement. the United Kingdom's fundamental monetary unit. known also as the pound sterling.
Given that A pound of strawberries costs $3.28
and a pound of apples costs $4.63
So the combined cost of 0.7 pound of strawberries and 1.4 pounds of apples is
cost = $3.28(0.7) + $1.4(4.63)
cost = $2.296 + $6.482
cost = $8.778
Therefore, the answer is $8.778.
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What is the result of adding the system of equations 2x y 4 3x y 6?
The addition of terms [tex]2x+y^4[/tex] and [tex]3x+y^6[/tex] will be [tex]5x+y^4+y^6[/tex]
A polynomial is an equation made up of variables, constants, and exponents that are mixed using mathematical operations including addition, subtraction, multiplication, and division (No division operation by a variable).
Simply add the coefficients of each phrase to add polynomials.
You may remove polynomials by subtracting the coefficients.
To add polynomials, just combine any like terms.
Step 1: Arrange each polynomial in decreasing order of degree, starting with the term with the highest degree.
Step 2: Sort the words that are similar. Similar phrases have the same variables and exponents.
So, the addition of terms [tex]2x+y^4[/tex] and [tex]3x+y^6[/tex] will be (2x+3x) (As here both are only the like terms, so they will be added together)
So, the sum will be: [tex]5x+y^4+y^6[/tex]
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The correct question should be:
What is the result of adding the system of equations:
[tex]2x+y^4[/tex] and [tex]3x+y^6[/tex]
What is the negation of ∃?
In order to find the negation of an expression we simply put the not operator in front of them . Therefore, the negation of ∃ is that â is not ^ to f.
The term negation means opposite , that is the negation of a statement is the opposite of the given mathematical statement. If we will take the example of P , let P be a statement, then the negation of P will be represented by ~P.
There are two symbols which are used to represent the negation of a statement which are “~” or “¬”. Therefore, ~P is known as the negation of P.
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The minimum hours of daylight occur mid-year with the maximum hours of daylight occuring in December.b.The maximum hours of daylight occur in January. The amount of daylight decreases each month until the minimum is reached in December.c.The minimum hours of daylight occur in December. The amount of daylight decreases each month until the minimum is reached.d.The minimum hours of daylight occur in January and December. The amount of daylight increases each month until it reaches a maximum mid-year.
The minimum hours of daylight occur in January and December is the correct answer . The amount of daylight increases each month until it reaches a maximum mid-year. Therefore, option D is correct.
The reason behind this is the rotation and revolution of Earth around the sun. The more the sun is towards the North Pole the shorter the day will be. On the equator, daylight will last generally for 12 hours as because sunlight falls directly on the equator
Therefore the shortest duration of daylight occurs in the month of December solstice when the North Pole is at its maximum distance from the Sun .
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A 140 meter rope is cut into two pieces. One piece is four time as long as the other. How long is each piece? Solve using substitution or elimination.
Answer:
28 m, 112 m
Step-by-step explanation:
x = length of short piece
4x = length of long piece
x + 4x = 140
5x = 140
x = 140/5 = 28
4x = 4(28) = 112
x+2y=3x+4 into y=mx+b form
x + 2y = 3x + 4
2y = 3x + 4 - x
y = (2x + 4)/2
y = x + 2
Answer: y=x+2
Step-by-step explanation:
you subtract x on the left on both sides then you'll have 2y=2x+4 we have to get y by itself so divide it by 2 on both side and when you do that on the right you divide both 2x and 4 by 2 thus giving y=x+2
An operator works a basic fortnight at a basic
rate of $8. 95 and earns $671. 25. Determine the
basic fortnight for the operator.
just the answer pls
To determine the basic fortnight for the operator, we need to divide the operator's earnings by their basic rate of pay.
$671.25 ÷ $8.95 = 75.05
The basic fortnight for an operator is the number of fortnights the operator has worked at their basic rate of pay. In this case, the operator has earned $671.25 at a basic rate of $8.95 per fortnight. To determine the basic fortnight, we need to divide the operator's total earnings by their basic rate of pay.
$671.25 ÷ $8.95 = 75.05
So, the operator has worked 75.05 basic fortnights. It means he has been working for 75.05*14=1053 days. This is the number of days the operator has worked at their basic rate of pay. It is important to note that this calculation assumes that the operator has not earned any overtime pay or other bonuses.
$671.25 ÷ $8.95 = 75.05
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After 2+3/2-x+1/3x have been combined using the least common denominator of 6x, what is the numerator?
On solving the provided question, we can say that In light of this, the lowest common denominator of the equation is (x - 4)(x + 1)(x - 2) (x - 2)
What is equation?An equation is a mathematical formula that connects two assertions using the equal sign (=) to denote equivalence. In algebra, an equation is a mathematical statement that establishes the equivalence of two mathematical expressions. For instance, an equal sign separates the components 3x + 5 and 14 in the equation 3x + 5 = 14. A mathematical formula is used to explain the connection between two sentences on either side of a letter. Frequently, there is just one variable, which is also the symbol. for example, 2x - 4 = 2.
equation is given as:
x2 — 3x — 4 = x2 — Ox + 8
x2 — 4x + x — 4 =
x(x — 4) + I(x — 4)
Factor out x - 4
(x + I)(x — 4) = x-2(x-4)
The common factor between the two sides of the equation is x – 4.
In light of this, the lowest common denominator is (x - 4)
(x + 1)(x - 2) (x - 2)
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(2, -4) and (-3, -3) write the linear equation in slope intercept form given the following
Answer:
y = -1/5x - 3.6
Step-by-step explanation:
(2, -4) and (-3, -3)
m = -3+4/ -3-2
m = 1/-5
m = -1/5
y = -1/5x + b
-4 = -1/5(2) + b
-4 = -0.4 + b
b = -3.6
y = -1/5x - 3.6
F(x)=\begin{cases}-2 & \text{ for }\hspace{10px} -6< x <-1\phantom{\frac{1}{1}} \\ -x-3 & \text{ for }\hspace{10px} -1< x <5\phantom{\frac{1}{1}}\end{cases} f(x)={ −2 −x−3 for −6
f(7) = 14 is calculated. Each function is given a domain and a codomain, or scope.
what is function ?The subject of mathematics includes quantities and their variations, equations and related structures, forms and their locations, and places where they can be found. The term "function" refers to the relationship between a set of inputs, each of which has an associated output. A relationship between inputs and outputs in which each input leads to a single, distinct result is known as a function. Each function is given a domain and a codomain, or scope. Usually, f is used to denote functions (x). input is an x. There are four main types of functions accessible. based on the following factors: on functions, one-to-one functions, many-to-one functions, within functions, and on functions.
given
We note that x=7 is on 1<x< 9 so we use the second piece. Replace x with 7 and
evaluate to find f(7):
f(7)=2(7)
f(7)=14
so f( 7 ) = 14
f(7) = 14 is calculated. Each function is given a domain and a codomain, or scope.
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help i cant solve it
Answer:
Step-by-step explanation:
We have,
x = 3y - 3 ---> x - 3y = -3 ------(1)
5x + 4y = 23 -----(2)
Multiplying eq. (1) by 5:
5x - 15y = -15 ------(3)
5x + 4y = 23
Subtracting (1) from (3):
-19y = - 38
y = 2
therefore, x - 6 = -3
x = 3
find the area of a rectangular garden with side length of 4x+11 and 2x+5
find the perimeter of the garden in the problem
Answer:
just ask your teacher for clarification, then you will actually learn...
A pendulum of length 1m and period 2.01s is placed at the top of Mount Everest
having an altitude of 8849m. Calculate the value of ‘g’ at that point.
Answer: A pendulum of length 1m and period 2.01s is placed at the top of Mount Everest having an altitude of 8849m. Calculate the value of 'g' at that point.
The period of this pendulum can be solved using the formula shown in the picture below. T is the period in seconds; L is the length in meters and g is the acceleration due to gravity which is equal to 9.81 m/s²near the equator.
T = 2 × π × (square root of 1.00 m / 9.81 m/s²)
T = 2 * 3.1416 * (square root of 0.101936799)
T = 6.2832 * 0.319275428
T = 2.00 seconds
The period of this pendulum correct to 3 significant figures is 2.00 seconds.
The frequency of this pendulum is solved by the formula f = 1/T
f = 1/2.00 seconds
f = 0.500 hertz
Answer: 9.76 m/s^2
Step-by-step explanation:
Melee has 1/8 of her candy bar left valid has 3/8 of his candy bar left if they put their candy together which fraction of candy bar do they have
Answer:
4/8
3/8 + 1/8 = 4/8
Please help!!! Very confused on my homework.
The tank is completely filled with water and then drains completely into the pool. The volume of the cylindrical tank is v1=36pir2/1 where r1 is the radius of the tank in feet.
PROBLEM IS ON THE ATTACHMENT!
Step-by-step explanation:
we need to use both equations for the volumes.
the only variables in them are r1 and r2.
when we say both results (volumes) are equal, that means we can create an equation with one formula on one side and the other formula on the other side.
and then we can easily transform the equation into "r1 = ..." or "r2 = ..."
and yes, your teacher made a mistake by hinting to solve for r1 in a. and b. it is r1 in a. and r2 in b.
a.
the goal here is an equation in the form
"r1 = ..."
that means r1 is a function of r2.
36×pi×r1² = 1/2 × 4/3 × pi × r2³ = 4/6 × pi × r2³ =
= 2/3 × pi × r2³
36 × r1² = 2/3 × r2³
r1² = (2/3 / 36) × r2³ = (1/(3×18)) × r2³ = 1/54 × r2³
r1 = sqrt(1/54 × r2³) = 1/3 × sqrt(1/6 × r2³)
b.
the goal here is
"r2 = ..."
again
36×pi×r1² = 2/3 × pi × r2³
36 × r1² = 2/3 × r2³
3×36 × r1² = 2 × r2³
3×18 × r1² = r2³
54 × r1² = r2³
[tex]r2 = \sqrt[3]{54 \times {r1}^{2} } = 3 \times \sqrt[3]{2 \times {r1}^{2} } [/tex]
c.
r2 is doubled.
so, we have to go back to our equation of a.
r1 = sqrt(1/54 × r2³).
when r2 is doubled, we get
r1 = sqrt(1/54 × (2×r2)³) = sqrt(1/54 × 8 × r2³) =
= sqrt(8) × sqrt(1/54 × r2³)
so, when r2 doubles, r1 has to grow by the factor of sqrt(8) to keep the equality intact.