Complete Question
A psychologist has designed an index to measure the social perceptiveness of elementary school children. The index is based on ratings of a child's responses to questions about a set of photographs showing different social situations. A random sample of 16 elementary school children was chosen, and their index measurements were recorded. Assume that the index measure in the population is normally distributed. The 95% confidence interval created from this data is (56.29, 65.09). This interval indicates:__________.Choose one or more:
a. The average index of elementary school children must be 60.69.
b. The standard deviation of the sample is about 10% smaller than the population standard deviation.
c. That if we take many samples from this population 95% of them will have a sample mean between 56.29 and 65.09.
d. 95% of all elementary school children in this district have indices between 56.29 and 65.09.
e. 4.40 is 95% of the true average of the index for all elementary school children.
f. We are 95% confident that the average index for all elementary school children is between 56.29 and 65.09.
Answer:
The correct option is a and f
Step-by-step explanation:
From the question we are told that
The sample size is n = 16
The 95% confidence interval is (56.29, 65.09)
Generally the sample mean(average index of elementary school children) is mathematically represented as
[tex]\= x = \frac{65.09 + 56.29}{2}[/tex]
=> [tex]\= x = 60.69 [/tex]
I'll send u the graph
Answer:
9
Step-by-step explanation:
2x3=6
3x3=9
I don't get how to do this, can someone help?
What is the second step in identifying grouped mean?
Answer:
B
Step-by-step explanation:
Divide the sum obtained in preceding step by total number of frequencies.
Can someone please help, ty!!
(Will mark brainliest)
Answer:
I believe it is four hours
Step-by-step explanation:
A national standard requires that public bridges over feet in length must be inspected and rated every 2 years. The rating scale ranges from 0 (poorest rating) to 9 (highest rating). A group of engineers used a probabilistic model to forecast the inspection ratings of all major bridges in a city. For the year 2020, the engineers forecast that % of all major bridges in that city will have ratings of 4 or below. Complete parts a and b. a. Use the forecast to find the probability that in a random sample of major bridges in the city, at least 3 will have an inspection rating of 4 or below in 2020. P(x3) nothing (Round to five decimal places as needed.)
Answer:
The answer is below
Step-by-step explanation:
A national standard requires that public bridges over 20 feet in length must be inspected and rated every 2 years. The rating scale ranges from 0 (poorest rating) to 9 (highest rating). A group of engineers used a probabilistic model to forecast the inspection ratings of all major bridges in a city. For the year 2020, the engineers forecast that 4%of all major bridges in that city will have ratings of 4 or below.
a. Use the forecast to find the probability that in a random sample of major bridges in the city, at least 3 will have an inspection rating of 4 or below in 2020.
Answer:
This problem is a probability binomial distribution and it can be solved using the formula:
[tex]P(X=x)=C(n,x)p^xq^{n-x}\\\\q=1-p,C(n,x)=\frac{n!}{x!(n-x)!}[/tex]
Hence the solution to the problem is given as:
P(x ≥ 3) = 1 - P(x < 3) = 1 - [ P(x=0) + P(x=1) + P(x = 2)]
Given that p = 4% = 0.04, q = 1 - p = 1 - 0.04 = 0.96, n = 10. Hence:
[tex]P(x=0)=C(10,0)*0.04^{0}*(0.96)^{10-0}=0.6648\\\\P(x=1)=C(10,1)*0.04^{1}*(0.96)^{10-1}=0.277\\\\P(x=2)=C(10,2)*0.04^{2}*(0.96)^{10-2}=0.0519\\\\P(x\geq 3)=1-[0.6648+0.277+0.0519]=0.0063[/tex]
PLEASE ANSWER I WILL MARK BRAINLEIST
The leg of a right triangle is 2 units and the hypotenuse is 5 units. What is the length, in units, of the other leg of the triangle?
Group of answer choices
3
Square root of 21
Square root of 29
7
Answer:
It is the Square root of 21
Step-by-step explanation:
what integer represents a gain of $9
If 125% of x is 225, what is the value of x?
Answer: 180
Step-by-step explanation: Try to find what 1% is, so do: 225/125, then you have 1%, now multiply that by 100 to find x. Your answer is 180.
Read the problem in the box below. Make a list to help you find the correct
answer.
Radio listeners were asked to call in and pick their
two favorite rodents. The listeners had 4 choices:
Woodchuck, Prairie dog, Beaver and Chipmunk.
Which of the following is the complete list of the
possible pairs of rodents?
A. WP, PW, WC, PB, PC, BP
0 0
B. WP, WB, WC, PB, PC, BW
C. WP WB, WC, PB, PC, BC
D. WP CB, WC, CP, PC, BC
Answer:
C. WP WB, WC, PB, PC, BC
Step-by-step explanation:
List the possible combinations. (With no duplicates)
WP, WB, WC
PB, PC
BC
Now check your options for the answer with the combinations you had.
That is your answer.
choose a linear function for the line representing by the point slope equation y-5=3(x-2)
Answer:
y=3x-1
Step-by-step explanation:
To find the linear function you first need to put the equation into standard slope intercept form which is y=mx+b. m represents the slope and b represents where the line intercepts the y axis.
To figure it out you need to solve for y.
y-5=3(x-2)
Expand 3(x-2) to 3x-6.
y-5=3x-6
Isolate the y by adding 5 to both sides, giving you y=3x-1.
The slope is 3 and the Y intercept is -1.
You have a box with dimensions 2 ft. x 4 ft. x 3 ft. a. If you want to wrap the box, what is the minimum amount of wrapping paper you need? b. If the paper cost $2.59 per square foot, what is the minimum cost?
Answer: A) 52 ft B) $134.68
Step-by-step explanation:
First find the surface area by multiplying the dimensions together.
2 x 4 = 8
2 x 3 = 6
4 x 3 = 12
Then add them up and multiply by two because there are two of each side.
26 x 2 = 52
To find the cost, multiply 52 by $2.59 to get the price.
52 x $2.59 = $34.68
Suppose we want to choose 6 letters, without replacement, from 12 distinct letters
?+7,785= $12,603
please help, I'm completely lost.
Answer:4818
Step-by-step explanation:7785-12603=4818
You borrow $600 to buy a violin. The simple interest rate is 15%. You
pay off the loan after 5 years. How much do you pay for the loan?
What would the monthly payment be for the loan?
Answer:
$1050
Step-by-step explanation:
$600*15%*5=$450 interest
interest+borrowed=loan
$450+$600=$1050
I don't know the monthly payment sorry
how do you simplify decimals??
ex) simplify.
7.21 + 4.2
Answer:
7.21+4.2
for 4.2 we can write it as 4.20 because 0 has no value after decimal point
then 7.21+4.20
by adding both we get 11.41
hope it helps you mate
please mark me as brainliast
Answer:
11.41
Step-by-step explanation:
7.21
+4.2
= 11.41
Solve 6.74x – 1.026 = 0.138. Round to the nearest thousandth. Show your work.
Answer:
x=0.173
Step-by-step explanation:
First thing I would do is add 1.026 to both sides. This would get you a equation that looked like, 6.74 x=1.164. Then just divide 1.164 and 6.74 by 6.74. This would get you x=0.1727003. Then because you have to round to the nearest thousand you have to round the 2 up because 7 is more then 5. Keep the first two number the same. The final answer is x=0.173.
A bucket is leaking. After 3 hours the bucket has leaked 6 gallons. How many gallons per hour is the bucket leaking?
Answer:
2 gallons
Step-by-step explanation:
divide 6 by 3 because that's the amount
Answer:
2 gallons
Step-by-step explanation:
The density curve below represents the number of hours that Mrs. Schultz's students spent studying for
their most recent test.
y
1
2
3
4 5 6
Which of the following statements are true?
Answer:
the mean of the study times is greater than the median
Step-by-step explanation:
456x5 please help me I don’t know how to work this out but I think you do 5x6 which is 30 than I don’t know after that??
Answer:
20,320
Step-by-step explanation:
6*5=30 PUT YOUR 3 UP AND KEEP THE ZERO ON BOTOM THEN 5*5 IS 25 PUT YOUR 2 UP AND YOUR 5 ON BOTTOM THEN 5*4= 20 PUT YOUR 2 UP AND 0 ON BOTTOM THEN PUT A ZERO UNDER YOUR FIRST 0 AND THEN TAKE 6*4= 24 PUT YOUR 2 UP AND YOUR 4 ON BOTTOM AND THEN TAKE 4*5= 20 PUT YOUR 2 UP AND 0 ON BOTTOM AND THEN TAKE 4*4 = 16 AND TAKE AND PUT YOU 1 UP AND YOUR 6 ON BOTOM AND ADD THEM TOGETHER
if i get £20 pounds at week and I need £470 pounds how many weeks do I have to save for
Answer:
23.5 weeks.
Step-by-step explanation:
470/20 is 23.5
Answer:
23.5 weeks or 24 weeks
Step-by-step explanation:
470/20 = 23.5
If you are not rounding to the next week, then its 23.5.
If you are rounding to the next week, then it should be 24.
Matek spends 4/5 of his homework time on math. He spends 1/12 of it on writing. What fraction of his homework time is spent on math or writing? Simplify the answer if possible.
Answer:
53/60 of his homework time
Step-by-step explanation:
We need to find 1/12 of 4/5, which can be calculated via the addition:
1/12 plus 4/5
1/12 + 4/5 = 5/60 + 48/60 = 53/60
So Matek spent 53/60 of his homework time on writing or math
On Monday joe bought 10 cups of coffee and 5 doughnuts for his office at the cost of $16.50. On Tuesday he bought 5 cups of coffee and 10 doughnuts for a total of 14.25. How much was each cup of coffee
Answer:
each cup cost 1.25 on Tuesday
Solve the system by substitution.
y=-x^2+2x+10
y=x+4
Answer:
x=3, y=7
x=-2, y=2
Step-by-step explanation:
System of Equations
We have the following equations:
[tex]y=-x^2+2x+10[/tex]
[tex]y=x+4[/tex]
We'll solve it by substitution. Since the second equation is already solved for y, we use that expression and substitute into the first equation:
[tex]x+4=-x^2+2x+10[/tex]
Since this is a quadratic equation, it's convenient to have all terms to one side:
[tex]x+4+x^2-2x-10=0[/tex]
Simplifying and reordering:
[tex]x^2-x-6=0[/tex]
Factoring:
[tex](x-3)(x+2)=0[/tex]
Solving:
x=3, x=-2
Those yield to two solutions for y:
y=x+4
y=7, y=2
The solutions of the system are:
x=3, y=7
x=-2, y=2
Given the following statement, what conclusion can be drawn using law of detachment?
If two angles are vertical, then they are congruent. Angles ABC and DBE are vertical.
Answer: Angles ABC and DBE are congruent
What are the opposites of 5, −2.4, 2.25, and 8 12 ? Enter the answers in respective order, each separated by comma.
Answer:
-5, 2.4, -2.25, -8, -12
Answer:
-5, 2.4, -2.25, -8, -12
Step-by-step explanation:
To make an number the opposite of itself you either make it a positive or negative. For example the opposite of 3 is -3 and the opposite of -3 is 3.
Brian May, guitarist for Queen, does not know how to price his signature Antique Cherry Special that cost him £340 to make. He knows he wants 80% markup on cost. What price should Brian May ask for the guitar?
9514 1404 393
Answer:
£612
Step-by-step explanation:
If Brian wants to add 80% of the cost to the cost, the selling price will be ...
£340(100% +80%) = £340·1.80 = £612
Brian May should ask £612 for the guitar.
Find the measure of each indicated angle. (2x-1) and (3x-19)
701, 752 rounded to 710,000
Does anyone know the answer to the question
Answer:
The root of that equation are -1 -4 and 5
so the equation is (x -5) * (x +1) * (x +4)
(I may have that wrong and the answer MIGHT be:
(x -+5) * (x -1) * (x -4)
So, you have 2 answers and I KNOW 1 of those is correct. :-)
Step-by-step explanation:
A triangle has vertices on the coordinate grid at points A(2, 4), B(2, 9) and C(5, 6) . What is the length, in units, of AB ?
Answer:
5 units long
Step-by-step explanation:
If you graph it, it is a simple straight line 5 units long between A and B.
You could also use the distance formula if you had to do more advanced distance calculations.
The distance formula is d=√((x2-x1)²+(y2-y1)²)