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]
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
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.
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
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.
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
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.
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.
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)
Can someone please help, ty!!
(Will mark brainliest)
Answer:
I believe it is four hours
Step-by-step explanation:
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
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)
Suppose we want to choose 6 letters, without replacement, from 12 distinct letters
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
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:
?+7,785= $12,603
please help, I'm completely lost.
Answer:4818
Step-by-step explanation:7785-12603=4818
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]
I'll send u the graph
Answer:
9
Step-by-step explanation:
2x3=6
3x3=9
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:
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:
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.
what integer represents a gain of $9
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
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:
I don't get how to do this, can someone help?
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.
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
701, 752 rounded to 710,000
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
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.