8. A substance has a half life of 2.347 minutes.
a. If the initial amount of the substance was 110.4 grams, how many half-lives will have passed
before the substance decays to 6.9 grams.
b. What is the total time of the decay?
Answer:
a.) 4 half lives have passed
b) 9.388 minutes
Step-by-step explanation:
Formula for exponential growth / decay is given as:
[tex]A=A_0b^{\frac{t}{c}}[/tex]
Where [tex]A[/tex] is the final population
[tex]A_0[/tex] is the initial population
[tex]b[/tex] is the growth factor
[tex]c[/tex] is the time taken for the growth 'b'
[tex]t[/tex] is the amount of time
Here, we are given that:
[tex]A[/tex] = 6. 9 grams
[tex]A_0[/tex] = 110.4 grams
[tex]b = \dfrac{1}{2}[/tex]
[tex]c = 2.347[/tex] min
To find:
a.) Number of half lives taken for the decay.
b.) Total time in the decay.
Solution:
a.) Number of half lives taken for the decay is nothing but equal to [tex]\frac{t}{c}[/tex].
Putting the values in the formula, we get:
[tex]6.9=110.4\times \frac{1}2^{\frac{t}{c}}\\\Rightarrow 6.9=110.4\times 0.5^{\frac{t}{c}}\\\Rightarrow 0.0625=0.5^{\frac{t}{c}}\\\Rightarrow \dfrac{t}{c} =4[/tex]
Therefore, the answer is:
4 half lives have passed.
b.) Total time of decay. We have to find the value of [tex]t[/tex] here.
From answer of part a.):
[tex]\dfrac{t}{c} =4\\\Rightarrow \dfrac{t}{2.347} =4\\\Rightarrow t =\bold{9.388\ min}[/tex]
On average, Seattle gets 38 inches of rain each year. How many centimeters of rain do they get each year?
I'll give brainiest!
Answer:
88.9
Step-by-step explanation:
For all x in the domain of the function (x+1)/(x^3-x) this func-
tion is equivalent to
Answer:
The function is equivalent to
[tex]\frac{x+1}{x^3-x}=\frac{1}{x\left(x-1\right)}[/tex]
Step-by-step explanation:
Given the function
[tex]f\left(x\right)=\frac{x+1}{x^3-x}[/tex]
Let us simplify this function
[tex]f\left(x\right)=\frac{x+1}{x^3-x}[/tex]
[tex]=\frac{x+1}{x\left(x+1\right)\left(x-1\right)}[/tex] ∵ [tex]Factor\:x^3-x=x\left(x+1\right)\left(x-1\right)[/tex]
Cancel the common factor (x+1)
[tex]=\frac{1}{x\left(x-1\right)}[/tex]
Therefore, the function is equivalent to
[tex]\frac{x+1}{x^3-x}=\frac{1}{x\left(x-1\right)}[/tex]
Answer:
wrong
Step-by-step explanation:
Zoe‘s graduation picnic cost $94 for the decorations plus an additional $10 for each attendee at Moose how many attendees can there be if Zoe budgets a total of $474 for her graduation picnic
Answer:
38 attendees.
Step-by-step explanation:
Subtract the cost of the decorations from the total (474 - 94). You are then left with $380 for all the attendees combined. Divide the total cost of attendees by the cost per attendee (380/ 10). You are left with 38 attendees. You can also check this backwards by multiplying 38 attendees by $10 (380), then adding the cost of decorations (94), and end up with the total cost of $474. I hope this helped!
Cameron spent 32 minutes on Instagram on Friday. The next day
he spent 30% of that on Instagram. In total, how much time did
Cameron spend on Instagram?
Answer:
41.6
Step-by-step explanation:
32 x 0.3 = 9.6
9.6 + 32 = 41.6
41.6
i had the same question
There are 60 new houses being built in a neighborhood. Last month, 1/4 of them were sold. This month, 1/5 of the remaining houses were sold. How many houses are left to be sold.
Answer:
36
Step-by-step explanation:
Number of new houses = 60
Number of houses sold last month = (1/4) of 60
[tex]= \frac{1}{4}*60[/tex]
= 15
Remaining houses = 60 - 15 = 45
Number of houses sold this month = (1/5) of 45
[tex]=\frac{1}{5}*45\\\\= 9[/tex]
Number of houses that are left = 45 - 9 = 36
For homework, a student had to complete 54 problems total. If she finished 9 problems in
class, what is the ratio of problems she still needs to complete to problems that she's
already finished?
Answer:
10
Step-by-step explanation:
Answer:
45:9
Step-by-step explanation:
Please please help me please it due today at 6:50pm please help will mark the brainiest please please help
Answer:
6. nebula
7. once the sun reaches the end of its life cycle it will become a white dwarf star
8. i cant see the rest fo the question
Step-by-step explanation:
hope this helps
The problems in this lesson review basic arithmetic skills.
Answer:
false
Step-by-step explanation:
Help pleaseee!
Thank you!
Answer:
The fourth graph
Step-by-step explanation:
PLEASE GIVE BRAINLIEST
What’s the numerator for the following rational expression please I need help quick taking test currently
Answer:
Well, the most reasonable explanation would be j+8 or 8+j
There is ounce of yeast in every 2 teaspoons of yeast. A recipe for bread calls for 2 teaspoons of yeast. How many ounces of yeast are needed for this recipe?
The following display from a TI-84 Plus calculator presents a 99% confidence interval for a proportion.Fill in the blanks: We are ________ confident that the population mean is between _______ and _______.a) 1%, 0, 0.583120b) 99%, 0, 0.583120c) 99%, 0.385631, 0.780609d) 1%, 0.385631, 0.780609
Answer:
The following display from a TI-84 Plus calculator presents a 99% confidence interval for a proportion.Fill in the blanks:
We are ____99%____ confident that the population mean is between ___0.385631____ and ___0.780609____.
c) 99%, 0.385631, 0.780609
Step-by-step explanation:
This is the only correct option, given the relevant population mean range. Option B is not correct as the population mean cannot range between 0 and 0.583120 as given by the option. Options 'a' and 'd' are not relevant to the question because they have 1% confidence level, instead of the stated 99% confidence level.
2 + 3 + 10029 + 12 + 34 x (14512 - 14511) = ?
Answer:
The answer is 10080
Step-by-step explanation:
Answer:
Step-by-step explanation:
2 + 3 + 10029 + 12 + 34 x (14512 - 14511) = 2+3+10029+12+34x1
=5+10029+12+34
=10080 answer
Write the equation of the line that passes through the point (-2, 7) and is PARALLEL to the line y = -4x + 1.
Answer:
The equation is [tex]y=x-9[/tex]
Step-by-step explanation:
If we want a line parallel to the line in the problem it will have the same slope. The equation given in the problem is already in slope intercept form so we can take the slope for the new equation directly from this equation.
The slope-intercept form of a linear equation is: [tex]y=mx+b[/tex]
Where m is the slope and b is the y-intercept value.
[tex]y=1x-2[/tex]
Therefore the slope is
[tex]m=1[/tex]
We can now use the point-slope formula to write the equation of the parallel line:
The point-slope formula states:
[tex](y-y1)=m(x-x1)[/tex]
Where m is the slope and [tex](x1,y1)[/tex] is a point the line passes through.
Substituting the information from the problem gives:
[tex](y- (-7)=1(x-2)[/tex]
[tex](y+7)=1(x-2)[/tex]
Or, we can solve for y to put the equation in slope-intercept form:
[tex]y+7=x-2[/tex]
[tex]y+7-7=x-2-7[/tex]
[tex]y+0=x-9[/tex]
[tex]y=x-9[/tex]
Find the distance of a line given the following points. R(3, 1), W(-1, -2)
Answer:
[tex]\sqrt{13}[/tex]
Step-by-step explanation:
we can solve this using the distance formula: [tex]\sqrt{(x_{2}-x_1)^{2} + (y_{2}-y_1)^{2}}[/tex]
[tex]x_1, y_1[/tex] is (3, 1)
[tex]x_2, y_2[/tex] is (-1, -2)
[tex]\sqrt{(1-3)^2 + (-2-1)^2}[/tex]
which simplifies to: [tex]\sqrt{(-2)^2 + (-3)^2}[/tex]
then: [tex]\sqrt{2^2 + 3^2}[/tex] or: [tex]\sqrt{4+9}[/tex]
your final answer is: [tex]\sqrt{13}[/tex] or about 3.61
I’ll give you a Brainly if you get this done in 3 mins -Solve each system by substitution
1) y=-3x+5
5x-4y=-3
2)y=-2
4x-3y=18
3)-7x-2y=-13
X-2y=11
4)-5x+y=-3
3x-8y=24
Answer:
1) x = 1 , y = 2
2) x=3, y=-2
3) x=3, y=-4
4) x=0, y=-3
Step-by-step explanation:
I hope this helped! please mark as brailiest
If 4 gal of the premium unleaded gasoline costs $16.24, how much would it cost to completely fill a tank whose capacity is 7 gal?
Answer:
$4.06 per gallon $4.06 x 7 = $28.42
Step-by-step explanation:
For this module's assignment review the following. 1. A student randomly guesses the answers to a four-question true-or-false quiz. The observation is the student's answer for each question. Write out the sample space. (Use T = true and F = false) 2. At Aunt Edna's Diner, a customer can choose from 5 appetizers, 7 entrees, 4 side dishes, and 6 desserts. How many different meals can be made by selecting one item from each course? 3. Compute gC3. 4. Compute 9P3-
9514 1404 393
Answer:
tttt, tttf, ttft, ttff, tftt, tftf, tfft, tfff fttt, fttf, ftft, ftff, fftt, fftf, ffft, ffff84084504Step-by-step explanation:
1. The sample space is all 16 possible sequences of T or F of length 4:
tttt, tttf, ttft, ttff, tftt, tftf, tfft, tfff fttt, fttf, ftft, ftff, fftt, fftf, ffft, ffff
__
2. The number of possibilities is the product of the numbers of choices at each stage:
5 × 7 × 4 × 6 = 840 . . . different meals
__
3. 9C3 = 9!/(3!·6!) = 84
__
4. 9P3 = 9!/6! = 504
Write the equation of the exponential function given two points: (1,6) (3,96)
Answer:
y = 3/2 ⋅ 4^x
Step-by-step explanation:
I hope this helped! please mark as brainliest
What's a rule you could apply to any number that would predict which denominators will terminate
9514 1404 393
Explanation:
The decimal equivalent of a fraction will terminate if its denominator can be factored using only the prime numbers 2 and/or 5.
1/4 = 1/(2·2) will terminate
1/15 = 1/(3·5) will not terminate
The 7th-grade class took a survey on their favorite ice cream. 58 people said they prefer vanilla, while 28 people said they prefer chocolate. Write a ratio comparing chocolate to vanilla. (Write it in a :b form)
Answer:
[tex]a : b = 14 : 29[/tex]
Step-by-step explanation:
Given:
[tex]Vanilla = 58[/tex]
[tex]Chocolate = 28[/tex]
Required
Represent as ratio
Let chocolate be represented with a and vanilla be represented with b
So, we have:
[tex]a : b[/tex]
[tex]a : b = 28 : 58[/tex]
Divide ratio by 2
[tex]a : b = 14 : 29[/tex]
Hence, the required ratio is [tex]14:29[/tex]
Find the equation of the line.
The perpendicular bisector to the line segment with endpoints (-8,5) and (4,1).
The equation of the line is
y =
Answer:
y = 3x + 9
Step-by-step explanation:
The perpendicular bisector to the line segment is passing through the midpoint of the line segment. Coordinates of midpoint are ( [tex]\frac{x_{1} +x_{2} }{2}[/tex] , [tex]\frac{y_{1} +y_{2} }{2}[/tex] )
Formula of slope is m = [tex]\frac{y_{2} -y_{1} }{x_{2} -x_{1} }[/tex]
Slopes of perpendicular lines are opposite reciprocals. So, if AB ⊥ CD , then [tex]m_{AB}[/tex] × [tex]m_{CD}[/tex] = - 1
y - [tex]y_{1}[/tex] = m ( x - [tex]x_{1}[/tex] )
~~~~~~~~~~~
(- 8, 5)
(4, 1)
m = ( 5 - 1) / ( - 8 - 4) = - [tex]\frac{1}{3}[/tex]
Opposite reciprocal to ( - [tex]\frac{1}{3}[/tex] ) is 3
Coordinates of midpoint are ( - 2 , 3 )
y - 3 = 3 ( x + 2 )
y = 3x + 9
Solve for indicated variable
Answer:dusy
Step-by-step explanation:
Answer:
h = SA/(2πr) - r
Step-by-step explanation:
From what I understood of the the statement, we have to solve the equation for the variable h. So, we just have to isolate that variable in one side. See:
[tex]SA = 2\pi r^2 + 2\pi rh\\\\2\pi rh = SA - 2\pi r^2\\\\h = \dfrac{ SA - 2\pi r^2}{2\pi r}\\\\\boxed{h = \dfrac{SA}{2\pi r} - r}[/tex]
Jack wants to attend a private 4-year university that costs $32,500 a year for tuition. His parents said they will give him $15,000 each year towards tuition. If he saves his money over the next four years before college, how much money will he have to save each year?
A $1,750
B $17,500
C $175
D $4375
Answer:
b
Step-by-step explanation:
4. If f(x) = 5X + 8, g(x) = 7X -2 Find (f - g)(x)
Answer:
-2x+10
Step-by-step explanation:
f(x)=5x+8
g(x)=7x-2
(f-g)(x)= 5x+8-7x+2= -2x+10
Please help I’m stuck on this question
the answer is b. the rest is so it can be enough charecters so i can post this answer
Please help...20 points! And explain
Brainliest be good peeps Calculate the missing term in each and for 2 its not 6/7 it cant be okay? thanks tho if you try and get that.
proportion.
2/11= /55
36/42= /
9/ = 21/28
6/9= /15
Answer:
The missing term is 10
Step-by-step explanation:
2/11=x/55
cross multiply
2*55=11x
x=10
I hope this helps :)
a rectangular poster is made up of an image surrounded by a border l, as shown below. the area of the image is 1347cm².what is the area of the border?
Answer:
i feel as though you have to multiply base times height
Step-by-step explanation:
you would have to multiply it