Answer:
The 95% confidence interval for the proportion of students who get coaching on the SAT is (0.1232, 0.147).
Step-by-step explanation:
In a sample with a number n of people surveyed with a probability of a success of [tex]\pi[/tex], and a confidence level of [tex]1-\alpha[/tex], we have the following confidence interval of proportions.
[tex]\pi \pm z\sqrt{\frac{\pi(1-\pi)}{n}}[/tex]
In which
z is the z-score that has a p-value of [tex]1 - \frac{\alpha}{2}[/tex].
427 had paid for coaching courses and the remaining 2733 had not.
This means that [tex]n = 427 + 2733 = 3160, \pi = \frac{427}{3160} = 0.1351[/tex]
95% confidence level
So [tex]\alpha = 0.05[/tex], z is the value of Z that has a p-value of [tex]1 - \frac{0.05}{2} = 0.975[/tex], so [tex]Z = 1.96[/tex].
The lower limit of this interval is:
[tex]\pi - z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.1351 - 1.96\sqrt{\frac{0.1351*0.8649}{3160}} = 0.1232[/tex]
The upper limit of this interval is:
[tex]\pi + z\sqrt{\frac{\pi(1-\pi)}{n}} = 0.1351 + 1.96\sqrt{\frac{0.1351*0.8649}{3160}} = 0.147[/tex]
The 95% confidence interval for the proportion of students who get coaching on the SAT is (0.1232, 0.147).
Find the focus of the parabola whose equation is y=1/8 x^2
Answer:
The focus is: [tex](0,2)[/tex]
Step-by-step explanation:
Given
[tex]y = \frac{1}{8}x^2[/tex]
Required
Determine the focus
The focus of a parabola
[tex](x- h)^2 = 4p(y - k)[/tex]
is:
[tex](h,k+p)[/tex]
So, we have:
[tex]y = \frac{1}{8}x^2[/tex]
Cross multiply
[tex]8y = x^2[/tex]
Rewrite as:
[tex]x^2 = 8y[/tex]
Rewrite as:
[tex](x - 0)^2 = 8(y - 0)[/tex]
Express 8 as 4 * 2
[tex](x - 0)^2 = 4 * 2(y - 0)[/tex]
By comparison with: [tex](x- h)^2 = 4p(y - k)[/tex]
[tex]h = 0[/tex] [tex]p =2[/tex] [tex]k = 0[/tex]
So, the focus [tex](h,k+p)[/tex] is:
[tex](h,k+p) = (0,0+2)[/tex]
[tex](h,k+p) = (0,2)[/tex]
A carpenter is designing rectangular picture frames to sell at a local craft fair. The frames will be made of wood with a uniform width around the picture, and each frame will have an opening for a 5-inch by 7-inch picture.
A jazz concert brought in $167,000 on the sale of 8,100 tickets. If the tickets sold for $15 and $25 each, how many of each type of ticket were sold?
Answer:
3,550 $15 tixkets and 4,550 $25 tickets were sold.
Step-by-step explanation:
15 × 3550=53250
25 × 4550=113750
53250+113750=167000
Quieres un chocolate?
Please help reply correctly in Spanish
Answer:
sí, (yo) quiero un chocolate
The mean of eight numbers is 41. The mean of two of the numbers is 29. What is the mean of the other six numbers
Answer:
45
Step-by-step explanation:
The mean is calculated as
mean = [tex]\frac{sum}{count}[/tex]
Given the mean of 8 numbers is 41 , then
[tex]\frac{sum}{8}[/tex] = 41 ( multiply both sides by 8 )
sum of 8 numbers = 328
Given the mean of 2 numbers is 29 , then
[tex]\frac{sum}{2}[/tex] = 29 ( multiply both sides by 2 )
sum of 2 numbers = 58
The sum of the remaining 6 numbers = 328 - 58 = 270 , so
mean = [tex]\frac{270}{6}[/tex] = 45
The mean of the other 6 numbers = 45
Find the surface area of the prism.
7 mm
4 mm
5 mm
Answer:
Since there are 2 sides, a front & back, and a top & bottom, you must find the surface area of each of those 3 surfaces and multiply by 2.
Step-by-step explanation:
The formula would be:
Top & Bottom - 5 × 4 (multiply by 2 for top AND bottom)
Front & Back - 5 × 7 (multiply by 2 for front AND back)
Sides - 4 × 7 (multiply by 2 for BOTH sides)
___________________________________________________
Once you find the 3 surface areas, add the areas all together for the total. (I did not show the answer because that is for you to do on your own.)
Ex. Top & Bottom + Front & Back + Sides
Answer:
166 is the answer.
PLEASE ANSWER! I don't understand this problem.
Answer:
The Domain is {3,2-1,0} Range {7,4,2}
Step-by-step explanation:
It is a function because there is one value of y for every x value.
Answer:
The Domain is: 3,2,-1,0.
The Range is: 7,4,2.
Step-by-step explanation:
The Domain is the first ones in the parentheses (x), and the range is the second ones in the parentheses (y).
Find the perimeter of quadrilateral ABCD. Round to the nearest tenth.
Kite A B C D on a coordinate plane with coordinates A 3 comma 5, B 1 comma 3, C 3 comma negative 1, and D 5 comma 3.
11.3 units
14.6 units
17.4 units
56.0 units
Answer:
14.6 units
Step-by-step explanation:
AB = [tex]\sqrt{(1-3)^2+(3-5)^2}[/tex]
AB =[tex]\sqrt{8}[/tex]
BC = [tex]\sqrt{(3-1)^2+(-1-3)^2}=\sqrt{20}[/tex]
CD = [tex]\sqrt{(5-3)^2+(3-(-1))} = \sqrt{20}[/tex]
DA = [tex]\sqrt{(5-3)^2+(3-5)^2} = \sqrt{8}[/tex]
Primeter = [tex]\sqrt{8} + \sqrt{20} + \sqrt{20} +\sqrt{8} = 14.6[/tex]
Help me please I don’t understand
=========================================
Explanation:
The perimeter around the circle, aka circumference, is found through this formula
C = 2*pi*r
That's for a full circle. However, we're dealing with semicircles here, so we cut that in half to get pi*r to represent the curved distance around half the circle.
For the outer larger semicircle, that curved distance is exactly 14pi
For the inner smaller semicircle, that curved distance is 7pi, since 7 is half of 14.
The total curved portions is 14pi+7pi = 21pi
Then we add on the last straight line portion that's 14 cm long to get a total perimeter of 21pi+14
This is the exact perimeter in terms of pi.
The last thing to do is replace pi with 3.14 and simplify
21pi+14 = 21*3.14+14 = 79.94
This value rounds to 80
A journey between two towns, Pietermaritzburg and Durban, is exactly 90 km 3.1 Use a graph (with at least 5 different speeds in km/h) to model how variation in speed (x) over the journey causes variation in time taken (y) to complete the trip.
Answer:
Speed in km/hr Time in Minutes
90 60
45 120
30 180
15 360
10 540
time Decrease when speed increase
Number of times the speed is increased the number of times time taken is reduced so it is not possible to take no time at all
as we can see from the graph that it is exponential , reduction in time keep reducing with increase in speed
Step-by-step explanation:
Can someone please help me on exercise 1.6, #2 (a to e). *Will report any spam answers* Thank you!
As shown in the picture, I sent two pictures.
-6 - (-8) x 5 ÷ (-10)
Answer:
- 10
Step-by-step explanation:
-6+8×5÷-10
-6+40÷-10
-6-4
-10
Answer and Step-by-step explanation:
According to PEMDAS (Parenthesis, Exponents, Multiplication, Division, Addition, Subtraction),
First we multiply, then divide, then finally add/subtract.
-8 times 5 is -40.
-40 divided by -10 is 4.
-6 - 4 = -10
The answer to the expression is -10.
#teamtrees #PAW (Plant And Water)
In two half-lives, how much of a 400-gram sample of a radioactive element will remain un-decayed?
Answer:
100 grams
Step-by-step explanation:
1/2 * 1/2 = (1/2)² = 1/4
1/4 * 400 = 100
What is the answer to this??
Answer:
C
Step-by-step explanation:
What is the perimeter of ABC?
Perimeter = ___ units.
Answer:
12 units
Step-by-step explanation:
From the given figure,
AB=4 units & BC=3 units
By Pythagoras Theorem, [tex]AC^{2} = AB^{2} + BC^{2}[/tex]
Here, [tex]AC^{2} = 4^{2} + 3^{2}[/tex]
Thus, AC=5 units
Now, perimeter of triangle is equal to the sum of all sides.
Perimeter = AB + BC + AC = 4 + 3 + 5 = 12 units
A committee must be formed with 3 teachers and 3 students. If there are 10 teachers
to choose from, and 15 students, how many different ways could the committee be
made?
Answer:
54,600 ways
Step-by-step explanation:
i hope you understand this
i need help please on this question
Look at the triangle below which of the following represents two of the angle measures of the triangle
Answer:
C. 60° and 80°
Step-by-step explanation:
Sum of triangle = 180°
Therefore,
8x + 4 + 6x - 2 + 10x + 10 = 180
Add like terms
8x + 6x + 10x + 4 - 2 + 10 = 180
24x + 12 = 180
24x = 180 - 12
24x = 168
x = 168/24
x = 7
Find each measure of the angles by substitute x = 7 into each expression
8x + 4 = 8(7) + 4 = 60°
6x - 2 = 6(7) - 2 = 40°
10x + 10 = 10(7) + 10 = 80°
The answer is 60° and 80°
Find the dimensions of a cube with a
volume of 125 cubic cm. (Hint: Remember
that a cube has equal dimensions
because all the sides are squares.)
5) 63 peaches in 7 bowls
Rate :
Unit Rate :
6) 480 hours of work in 12 weeks
Rate :
Answer:
9 peaches per bowl
40 hours each week
Answer:
Your mom
Step-by-step explanation:
tan(pi/2)=_
A. -1
B. 0
C. 1
D. Undefined
AP3X
Answer:
I don't know the answer
Step-by-step explanation:
c.1
The following ordered pairs represent a function. (-2,-1) (-1,0), (0,1), (1,2), (2,3)
help quick
Answer:
c
Step-by-step explanation:
your welcome! :) ❤❤❤❤❤❤❤❤❤❤❤❤
3/4(2x-6)-2(1/2x+1)-1+5x
Answer:
Distribute:
=(
3
4
)(2x)+(
3
4
)(−6)+(−2)(
1
2
x)+(−2)(1)+−1+5x
=
3
2
x+
−9
2
+−x+−2+−1+5x
Combine Like Terms:
=
3
2
x+
−9
2
+−x+−2+−1+5x
=(
3
2
x+−x+5x)+(
−9
2
+−2+−1)
11
2
x+
−15
2
Step-by-step explanation:
If a cube measures 13 cm each and the volume is 2197 what is the surface area of the cube
Answer:
1014 cm^2
Step-by-step explanation:
A cube has 6 congruent square faces. To find the total surface area, find the surface area of one face,a nd multiply it by 6.
SA = 6s^2
SA = 6(13 cm)^2
SA = 6(169 cm^2)
SA = 1014 cm^2
Candace invests $636 in an investment that pays 7% interest compounded quarterly. What is her annual effective yield? Input answer as a percentage to two decimal places.
Answer:
7.19%
Step-by-step explanation:
let i be the effective rate
[tex](1+\frac{.07}{4})^4=(1+i)\\.071859031[/tex]
The annual effective yield will be 7.19% for the investment.
What is compound interest?Compound interest, also known as interest on principal and interest, is the practice of adding interest to the principal amount of a loan or deposit.
Given that Candace invests $636 in an investment that pays 7% interest compounded quarterly.
The annual effective yield will be calculated as below:-
[ ( 1 + ( 0.07 / 4 )⁴ ] = ( 1 + i)
Solve the equation:-
i = 0.0718
i = 0.0718 x 100 = 7.19%
Therefore, the annual effective yield will be 7.19% for the investment.
To know more about compound interest follow
https://brainly.com/question/24924853
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If post are space 5 feet apart and how many posts are needed for 60 feet of straight line fence
Step-by-step explanation:
Math is a language
say you plant two posts that are 5ft apart and you want to get up to 60ft
right now you've covered 5ft and now have 60 - 5 = 55ft to go.
you plant the next one: 55 - 5 = 50ft to go
instead of subtracting many times and counting hiw many times we've subtracted, we can use division
60ft / 5ft = 12 posts
to verify, you can multiply 5 and 12 which is the same as adding 5 + 5 + 5 + 5 +... + 5 = 5ft x 12 Posts= 60ft in total length
There are 12 posts for 60 feet of straight line fence.
Here,
Given that,
Post are space 5 feet apart.
We have to find number of posts for 60 feet of straight line fence.
What is Division method?
This method of distributing a group of things into equal parts is termed as division.
Now,
We can division method to find number of posts for 60 feet of straight line fence.
Here, Post are space 5 feet apart.
Number of posts = [tex]\frac{60}{5} = 12[/tex]
Hence, There are 12 posts for 60 feet of straight line fence.
Learn more about the Division method visit:
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can someone help me with this please
Answer:
B
Step-by-step explanation:
This is because the difference of two squares follows the general equation of (x-a)^2 - a^2 - c
Answer:
It's a
Step-by-step explanation:
[tex] \frac{1}{4} {x}^{2} - 1[/tex]
[tex]{( \frac{1}{2} x)}^{2} - {1}^{2} [/tex]
Find X round to the nearest 10th 21 and 52°
Answer:
x is triangle
Step-by-step explanation:
sudsy baka
You want to buy a new lawn chair from Bed Bath & Beyond that costs $149.99. Luckily you have a coupon for 20% off. Write an expression that could be used to find the sale price of the lawn chair.
No links or I will report!
Answer:
The sale price of the lawn chair is $119.992
Step-by-step explanation:
149.99 times 0.2=29.998
Subtract
149.99-29.998=119.992
Hope I helped :)
Help plzzz and no links plz and thank you
Answer:
It's B, Points a and f. -5 and 5
