Answer:
a) c. 90.
b) The margin of error of the point estimate is of 6.19 minutes.
c) The minimum sample size needed to obtain this amount of precision is 289.
Step-by-step explanation:
(a) Which of the following numbers gives the value of the point estimate?
The value of the point estimate is the sample mean, of 90 minutes. So the answer is given by option c.
(b) Using the information given above, calculate the margin of error (in minutes) of the point estimate. Assume we would like to estimate the population mean with 95% confidence.
We have the standard deviation for the sample, which means that the t-distribution is used to solve this question.
The first step to solve this problem is finding how many degrees of freedom, we have. This is the sample size subtracted by 1. So
df = 25 - 1 = 24
95% confidence interval
Now, we have to find a value of T, which is found looking at the t table, with 24 degrees of freedom(y-axis) and a confidence level of [tex]1 - \frac{1 - 0.95}{2} = 0.975[/tex]. So we have T = 2.0639.
The margin of error is:
[tex]M = T\frac{s}{\sqrt{n}}[/tex]
In which s is the standard deviation of the sample and n is the size of the sample.
Here, we have [tex]s = 15, n = 25[/tex]. So
[tex]M = T\frac{s}{\sqrt{n}}[/tex]
[tex]M = 2.0639\frac{15}{\sqrt{25}}[/tex]
[tex]M = 6.19[/tex]
The margin of error of the point estimate is of 6.19 minutes.
Question c:
College students tend to watch sports between 0 and 120 minutes per day, which means that the standard deviation for population can be estimated as the standard deviation of an uniform distribution with [tex]a = 0, b = 120[/tex]. This standard deviation is:
[tex]\sigma = \sqrt{\frac{(b-a)^2}{12}}[/tex]
Then
[tex]\sigma = \sqrt{\frac{(120-0)^2}{12}}[/tex]
[tex]\sigma = 34.64[/tex]
Minimum sample size:
Now, since we have an estimate for the standard deviation of the population, we use the z-distribution.
We have that to find our [tex]\alpha[/tex] level, that is the subtraction of 1 by the confidence interval divided by 2. So:
[tex]\alpha = \frac{1 - 0.95}{2} = 0.025[/tex]
Now, we have to find z in the Ztable as such z has a pvalue of [tex]1 - \alpha[/tex].
That is z with a pvalue of [tex]1 - 0.025 = 0.975[/tex], so Z = 1.96.
Now, find the margin of error M as such
[tex]M = z\frac{\sigma}{\sqrt{n}}[/tex]
In which [tex]\sigma[/tex] is the standard deviation of the population and n is the size of the sample.
The minimum sample size is n for which M = 4. So
[tex]M = z\frac{\sigma}{\sqrt{n}}[/tex]
[tex]4 = 1.96\frac{34.64}{\sqrt{n}}[/tex]
[tex]4\sqrt{n} = 1.96*34.64[/tex]
[tex]\sqrt{n} = \frac{1.96*34.64}{4}[/tex]
[tex](\sqrt{n})^2 = (\frac{1.96*34.64}{4})^2[/tex]
[tex]n = 288.1[/tex]
Rounding up:
The minimum sample size needed to obtain this amount of precision is 289.
PLEASE ANSWER ASAP WILL MARK BRAINLIEST!!
There are 5 red marbles, 15 blue marbles, and 5 green marbles in a bag. You reach in and randomly draw a marble,
replace it, and draw another marble. What is the probability that the first will be red and the second will be blue?
a.) 20%
b.) 80%
c.) 8%
d.) 12%
Answer: Hope This Helps!
Step-by-step explanation:
I would estimate around 8% or 12% is the answer. Red Marbles are a small percentage and the chance it will be picked instead of something else is rare however blue marbles are the most common and chance one will be picked is fairly high.
rotate the object 90 degrees around the origin. What are the new coordinates?
Answer:
s
Step-by-step explanation:
d
Can you please help me
Answer:
is there amultipe choice answer if so list them down
Step-by-step explanation:
What is the area of the sector for the following circle? Round your answer to 4 decimal places. *
Answer:
Area = 13.0900 ft²
Step-by-step explanation:
Area of sector = θ/360 × πr²
We are assuming it's the area of the minor sector that we are asked to find.
Therefore,
θ = 360 - 300 = 60°
r = 5 ft
Plug in the values
Area of minor sector = 60/360 × π × 5²
Area = 13.0899694
Area = 13.0900 ft² (to 4 decimal places)
Step-by-step explanation:
The angle of the minor sector will be ,
> 360 - 300 = 60° .
Area of sector :-
> Area = ∅ / 360 × πr²
> A = 60/360 × 3.14 × 5ft²
> A = 13.09 ft²
When oil is spilled in water, it creates a thin film of water approximately 1 micron thick. A barrel of oil is approximately 42 gallons of oil. If we spill a barrel of oil on the water, what is the area covered by the oil slick
Draw a sketch showing the relevant dimensions.
State your answer in square meters.
State your answer in square kilometers.
9514 1404 393
Answer:
158,987 m²0.158986 km²Step-by-step explanation:
42 gallons is about 0.158987 cubic meters. 1 micron is 1 micro-meter, or 10^-6 meters. The volume is the product of the area and thickness. For some area A, we have ...
0.158987 m³ = (10^-6 m)A
A = (10^6)(0.158987 m² = 158,987 m²
The area in square meters is 158,987.
__
A square km is (1000 m)² = 10^6 m². So, the area in square kilometers is about ...
(158,987 m²)/(10^6 m²/km²) = 0.158987 km²
The area in square km is about 0.1590.
(3^6/7^-3)= Please I need help!!!
Answer: [tex]\frac{243}{7}[/tex]
Steps:
[tex]\frac{3^6}{7^-\cdot \:3}[/tex]
[tex]\mathrm{Cancel\:the\:common\:factor:}\:3[/tex]
[tex]=\frac{3^5}{7}[/tex]
[tex]3^5=243[/tex]
[tex]=\frac{243}{7}[/tex]
Hope This Helps!
Help meeeeeee ASAP helppppppp
Answer:
45 × 1/3 = 15
Step-by-step explanation:
15 / (1/3) = (3×15)/1 = 45
so, from 15 / (1/3) = 45
we can then adapt the equation by multiplying both sides by 1/3
15 = 45 × (1/3)
Find the value of x. NO LINKS!!!
9514 1404 393
Answer:
z° = 44°
Step-by-step explanation:
The sum of angles in a triangle is 180°.
44° +52° +z° +40° = 180°
z° = 44° . . . . . . . . . . . . . . . . subtract 136° from both sides
The value of z is 44.
_____
There is no "x".
Now we have to,
→ find the required value of z.
The equation is,
→ A + B + C = 180°
Let's solve for the value of z,
→ A + B + C = 180°
→ (52 + z) + 44 + 40 = 180
→ 136 + z = 180
→ z = 180 - 136
→ [ z = 44° ]
Hence, the value of z is 44°.
Help!! If anyone could help, I’ll give Brainly! :) thank you so much
9514 1404 393
Answer:
$50
Step-by-step explanation:
The compounding period is 1 year, and the period of concern is 1 year. This means the simple interest formula will tell the answer to the question.
I = Prt
I = ($5000)(0.01)(1) . . . . . r = annual rate; t = years
I = $50
The interest earned in the account is $50.
Reese used a $60 Amazon gift card to buy stickers for her friends. After paying for 12 stickers, her balance on the gift card was $18. What was the price of each sticker, assuming all the stickers cost the same amount?
Answer:
3.5 dollars per sticker
Step-by-step explanation:
60 - 18 = 42
42 ÷ 12 = 3.5
I think this is the correct but it may be not , sorry if I wasn't that helpful...
Javier is buying oak flooring for the living room. How many square feet of flooring does he need to buy?
18 ft
9 ft
BRO
A 162 ft2
B 54 ft2
C 27 ft2
O D. 1812
PLEASE HELP ILL MARK YOU AS BRAINLESS
54 ft.
Step-by-step explanation:
add 18 on both sides which is 36. then do that with 9 9+9=18 and 18+18=36 36+18=54.
to bake a cake, the recipe calls for 6 eggs. Arline wants to bake 24 cakes for her schools bake sale. how many eggs will she need in all for the 24 cakes?
Answer:
144 eggs
Step-by-step explanation:
1 cake = 6 eggs
24 * 6 = 144 eggs in total.
A longer way to do it is by adding 6, 24 times.
6+6+6+6+6+6+6+6+6+6+6+6+6+6+6+6+6+6+6+6+6+6+6+6 = 144
But by multiplying, it makes it easier to find the answer.
What is the volume of the box
Answer:
Volume = 144 in.³
Step-by-step explanation:
Given:
Length = 9 in.
Width = 4 in.
Height = 4 in.
Required:
Volume
Solution:
Volume of a box = length * height * width
Volume = 9*4*4
= 144 in.³
4 (x + 2.5) = 48
Explain your reasoning as well.
Answer: 9.5 is the answer. You have to distribute through.
Explain: 4x+10=48
Subtract 10 from both sides you get 4x=38. Then divide both sides by 4 you get 9.5.
I need help asap:
Seventh-grade students at two different schools took the same math test at the end of the school year. Their results are shown below.
The school counselors are planning the numbers of different math classes for these students when they enter eighth grade. Which statement best describes the plan they should follow, based on the information shown?
A
School 1 should have a greater variety of math classes, since the interquartile range is much smaller than at school 2.
B
School 2 should have a greater variety of math classes, since the median is higher than at school 1.
C
School 2 should have a greater variety of math classes, since the interquartile range is much greater than at school 1.
D
School 1 should have a greater variety of math classes, since the median is lower than at school 2
Answer:
its C
Step-by-step explanation:
School 1 IQR = 10
School 2 IQR = 20
Both have a median of 80
School 2
First Quartile:
70
Third Quartile:
90
School 1
First Quartile:
75
Third Quartile:
85
Please Brainiest!
Need help fast.
A pool is shaped like a rectangle with a length of 4 times its width w. What is an
expression for the distance between opposite corners of the pool?
No links or files!!!
w represents width
4w represents length
d represents diagonal
w2 + (4w)2 = d2
w2 + 16w2 = d2
17w2 = d2
±w√17 = d
The diagonal is the width times √17.
What is the lateral surface area, in square inches, of the figure formed by the net?
Answer:
71 in²
Step-by-step explanation:
surface area = (4×6)+(2×½×4×5)+(2×½×6×4.5)
= 24+20+27 = 71 in²
PLZZ HELP!!!
Which graph shows the solution to the system of equations 2x + y = 4 and 3x - 2y = 6?
Answer:
the last one
Step-by-step explanation:
__________________
The product n and sum of n and 76
Answer:
n+76
n --> a number not determined (and a random product)
76 --> the number the problem gave
+ --> required for addition, which provides the sum
Please answer number 9 I’ll give brainliest
Answer:
2/3 or 66.7%
Step-by-step explanation:
there are 6 possible options. 2 of them are red. 6 options minus 2 = 4=4/3=2/3
20. Miguel started with $50
in his bank account. He
deposited $20. The next day
he withdrew $40. How much
is in his bank account?
Answer:
-$10
Step-by-step explanation:
50-20=
30
30-40
= -10
What is the volume of the rectangular prism? Help pls
Answer:
10ft³
Step-by-step explanation:
3 x 5 x 2 = 30
30 x 1/3 = 10ft³
6 times the difference between q and 1
Answer:
6q-1. It's not factorsble with rational mumbers.
Answer:
6q - 6
Step-by-step explanation:
6 x (q - 1) =
6 x q - 6 x 1 =
6q - 6
Hope that helps! :)
-Aphrodite
99 is decreased to 44
Answer:
99 -? = 44.
99 -a = 44.
99 -44 -a = 44-44.
55 = a.
The interest for a bank account is compounded quarterly. The equation 480(1.08)12 is used to calculate the value of the account after some amount of time.
The yearly interest rate for the account is
8%
3%
2%
32%
12%
Answer:
8%
Step-by-step explanation:
1.08 is an increase of 0.08, which is 8%
Answer: 3%
Step-by-step explanation:
since the total amount ended up being 12 your going to divide by 4 which is the quartly amount which is how u end up with 3%.
what expressions are equivalent to 1/5•1/5•1/5•1/5
Answer:
Step-by-step explanation: Because equivalent expressions is when you Combine any like terms on each side of the equation: x-terms with x-terms and constants with constants. Arrange the terms in the same order, usually x-term before constants. If all of the terms in the two expressions are identical, then the two expressions are equivalent.
PLEASE HELP Amber has 7 books to read. She will read 1/2 of a book each day. How many days will it take Amber to read all 7 books?
Answer:
14 days
Step-by-step explanation:
Help me HOW which choice is it
number 3 is correct
Step-by-step explanation:
smaller<bigger
The radius of a circle is 7 cm. Enter the circumference of the circle, in cm. Round your answer to the nearest hundredth.
Answer:
C = 43.98cm. This answer was taken online
Answer:43.98
Step-by-step explanation: Circumfernce = 2 pi r.So what we have to so is first 7(2) = 14 Next we multiply 14 by pi which is about 43.98229... Now we have to round to the nearest hundredth which is two place after the decimal point. So 8 is the number we are rounding. If we look to the right of 8 the number is 2. Anything below 5 we keep the number the same. There you have it your answer will be 43.98
what is the volume of a bow with a width of 3/2 inches a length of 5/2 inches and a height of 4 inches
Answer:
v=LxWxH
v= 3/2x5/3x4
v=15/6x4
v=10in³