Answer:
7 7/12
Step-by-step explanation:
A pew research Center project on the state of news media showed that the clearest pattern of news audience growth in 2012 came on digital platforms. According to pew research data, 39% of Americans get news online or from a mobile device in a typical day. a. Suppose that you take a sample of 100 Americans. If the population proportion of Americans who get news online or from a mobile device in a typical day is 0.39, what is the probability that fewer than 30% in your sample will get news online or from a mobile device in a typical day? b. Suppose that you take a sample of 400 Americans. If the population proportion of Americans who get news online or from a mobile device in a typical day is 0.39, what is the probability that fewer than 30% in your sample will get news online or from a mobile device in a typical day? c. Discuss the effect of sample size on the sampling distribution of the proportion in general and the effect on the probabilities in (a) and (b).
Answer:
Step-by-step explanation:
Given that:
the sample proportion p = 0.39
sample size = 100
Then np = 39
Using normal approximation
The sampling distribution from the sample proportion is approximately normal.
Thus, mean [tex]\mu _{\hat p} = p = 0.39[/tex]
The standard deviation;
[tex]\sigma = \sqrt{\dfrac{p(1-p)}{n} }[/tex]
[tex]\sigma = \sqrt{\dfrac{0.39(1-0.39)}{100} }[/tex]
[tex]\sigma = 0.048[/tex]
The test statistics can be computed as:
[tex]Z = \dfrac{{\hat _{p}} - \mu_{_ {\hat p}} }{\sigma_{\hat p}}[/tex]
[tex]Z = \dfrac{0.3 - 0.39 }{0.0488}[/tex]
[tex]Z = -1. 8 4[/tex]
From the z - tables;
[tex]P (\hat p \le 0.3 ) = P(z \le -1.84)[/tex]
[tex]\mathbf{P (\hat p \le 0.3 ) = 0.0329}[/tex]
(b)
Here;
the sample proportion = 0.39
the sample size n = 400
Since np = 400 * 0.39 = 156
Thus, using normal approximation.
From the sample proportion, the sampling distribution is approximate to the mean [tex]\mu_{\hat p} = p = 0.39[/tex]
the standard deviation [tex]\sigma_{\hat p} = \sqrt{\dfrac{p(1-p)}{n} }[/tex]
[tex]\sigma_{\hat p} = \sqrt{\dfrac{0.39 (1-0.39)}{400} }[/tex]
[tex]\sigma_{\hat p} =0.0244[/tex]
The test statistics can be computed as:
[tex]Z = \dfrac{{\hat _{p}} - \mu_{_ {\hat p}} }{\sigma_{\hat p}}[/tex]
[tex]Z = \dfrac{0.3 - 0.39 }{0.0244}[/tex]
[tex]Z = -3.69[/tex]
From the z - tables;
[tex]P (\hat p \le 0.3 ) = P(z \le -3.69)[/tex]
[tex]\mathbf{P (\hat p \le 0.3 ) = 0.0001}[/tex]
(c) The effect of the sample size on the sampling distribution is that:
As sample size builds up, the standard deviation of the sampling distribution decreases.
In addition to that, reduction in the standard deviation resulted in increases in the Z score, and the probability of having a sample proportion that is less than 30% also decreases.
11 2/8 - 5 1/2 • 1 2/3 + 1 1/4
Answer:
[tex]3\frac{1}{3} = \frac{10}{3} = 3.333333333[/tex]
Step-by-step explanation:
Hope this helps.
WILL MARK BRAINLIEST ONLY HAVE 10 MINUTES AND DOUBLE POINTS
Hey there!
They are both correct, and their expressions are equivalent.'
9(S + T) + 45 = 9S + 9T + 45
Have a terrificly amazing day!
7.5 miles in 1/2 hour at a constant speed
Answer:
Okayyy then...........
A sheet of standard U.S. typing paper measures 8.50 in by 11 in. What is its area in square centimeters? (Area =L x W)
Answer:
the area would be 935cm
Step-by-step explanation:
ty for reading :P
603.2246 square centimeters.
PLZ HELP ME
Match the verbal expression (term) with its algebraic expression (definition).
DUE IN 20 MINUTES
Match Term Definition
Four less than an unknown value A) z ÷ 4
Quotient of a variable and four B) a4
Some number to the power of four C) 4x
Four times an unknown value D) b + 4
Four more than some number E) y − 4
Answer:
Four less than an unknown value: E
Quotient of a variable and 4: A
Some number to the power of four: B
Four times an unknown value: C
Four more than some number: D
Step-by-step explanation:
You honestly could do it by yourself, it just consists of matching the operation
What is the value of W in the equation 1/4W=16
Answer:
w=64
Step-by-step explanation:
you just have to multiply 4 on both sides to cancel the 1/4, and 16x4=64
Answer:
W = 64Step-by-step explanation:
We will undo the operations that obscure the value of W to find its value.
1/4W = 16
Since we divided W by 4 (1/4W is the same a W/4), we will multiply both sides by 4.
16 x 4 = 64.
The value of W is 64.
Find the simple interest on a P10500 loan at 20% for two years. (show
your process to get two points)
DO
D12
Dan
Answer:
P4200
Step-by-step explanation:
SI=PRT/100
P=Principal which is P10500
R=Rate which is 20%
T=Time which is 2 years
So SI= 10500×20×2/100
=P4200
Find two angles (in radians) whose sine ratio is...
Hi there!
[tex]\large\boxed{\frac{\pi}{3} \text{ and } \frac{2\pi}{3}}[/tex]
From the unit circle, we can locate the two values of sine Ф (y-value of the coordinate) at which sin Ф = √3/2.
The two values are Ф = π/3 and 2π/3.
Find the slope and y-intercept
b. y = 1/4x - 6
Answer:
Slope: 1/4
y-intercept: -6
Step-by-step explanation:
The answer is (0, -6)
Mai Finished her math assignment 3/5 hours. then she completed her English assignments in 1/3 hours. what was the total amount of time Mai spent doing these two assignments?
good review if you answer with the right answer
Answer:
top left choice
Step-by-step explanation:
the slope is negative, so its flipped
the y int is -6, below the x axis
Answer:
Graph A (the top left)
Step-by-step explanation:
The correct graph has to have a negative slope. So this narrows the options down to either A (top left) or B (top right). The y-intercept has to be negative, and out of A and B, only Graph A meets this requirement.
Hope it helps!
A calculator is required to obtain the final answer on this question. A solid metal sphere at room temperature 20oC is dropped into a container of boiling water (100oC). If the temperature of the sphere increases 10o in 9 seconds, find the temperature of the ball after 18 seconds in the boiling water. (Assume the sphere obeys Newton's Law of Cooling.)
Answer:
38.71°C
Step-by-step explanation:
Given :
Initial temp, T0 = 20°C
Final temperature, T = 20 + 10 = 30°C
Time, t = 9 seconds
Surrounding temperature, Ts = 100°C
Newton's Law of cooling :
T = Ts + (T0 - Ts) * e^-kt
Obtain the value of k
30 = 100 + (20 - 100) * e^-9k
30 - 100 = - 80e^-9k
-70 = - 80e^-9k
-70 / - 80 = e^-9k
0.875 = e^-9k
Take the In of both sides
In(0.875) = - 9k
−0.133531 = - 9k
k = 0.133531 / 9
k = 0.0148
Hence,
t = 18
T = Ts + (T0 - Ts) * e^-kt
T = 100 + (20 - 100) * e^-0.0148(18)
T = 100 - 80 * e^-0.0148(18)
T = 100 - 80 * 0.7661326
T = 38.709392
T = 38.71°C
I'm doing a test and I need to know which one right I'll attach a photo of it it's a simple one I just want a second opinion.
Answer:
B.
Step-by-step explanation:
What is the sum
X+
1
دیا |
x
100
Uw
x+
ოjთ
3 5
O 5*+
3 7
X+
8
Answer:
use photo math lol
Step-by-step explanation:
A pharmacist found at the end of the day she had 3/2 as many prescriptions for antibiotics as tranquilizers. She had 35 prescriptions altogether. How many did she have for tranquilizers?
Answer:
She had 14 prescriptions for tranquilizers.
Step-by-step explanation:
This question can be solved using a system of equations.
I am going to say that:
x is the number of prescriptions she had for antibiotics.
y is the number of prescriptions she had for tranquilizers.
A pharmacist found at the end of the day she had 3/2 as many prescriptions for antibiotics as tranquilizers.
This means that:
[tex]\frac{x}{y} = \frac{3}{2}[/tex]
[tex]x = \frac{3y}{2}[/tex]
She had 35 prescriptions altogether.
This means that:
[tex]x + y = 35[/tex]
How many did she have for tranquilizers?
We want to find y. Since [tex]x = \frac{3y}{2}[/tex], we solve the following equation.
[tex]x + y = 35[/tex]
[tex]\frac{3y}{2} + y = 35[/tex]
Multiplying everything by 2
[tex]3y + 2y = 70[/tex]
[tex]5y = 70[/tex]
[tex]y = \frac{70}{5}[/tex]
[tex]y = 14[/tex]
She had 14 prescriptions for tranquilizers.
whats the domain? someone pleaseee
A quality assurance check is 97% accurate for non-defective devices and 88% accurate for defective devices. Of the devices checked, 92% of devices are not defective. What is the probability of an incorrect conclusion? Round your answer to the nearest tenth of a percent.
Answer:
so 3 percent of 92 percent which is 2.76 percent
ANSWER PLEASE..................
Determine the value of x in the figure
Answer:
it’s C x=65
Step-by-step explanation:
There were 144 books about mammals in the library. If the ratio of books about mammals to books about plants was 9 to 8, how many books about plants were in the library?
Suppose there is a simple index of three stocks, stock X, stock Y, and stock Z.
Stock X opens the day with 5000 shares at $4.30 per share. Stock Y opens
the day with 2000 shares at $3.20 per share. Stock Z opens the day with 8000
shares at $4.90 per share. This simple index rises 4.9% over the course of the
day. What is the value of the index at the end of the day? Round your answer
to the nearest hundred.
A. $68,700
B. $67,100
C. $70,400
D. $68,300
Answer:
C
Step-by-step explanation:
so the first one ends at 4.7107
the second- 3.3568
the third- 5.1401
and multiplying the first by 5000 we get- 23,553.5
for the second we get -6,713.6
for the third we get 41,120
adding them all together we get 71,387.1
and so C is the closest
The value of the index at the end of the day should be considered as the $70,400.
Calculation of the value of the index:Since
Stock X opens the day with 5000 shares at $4.30 per share.
Stock Y opens the day with 2000 shares at $3.20 per share.
Stock Z opens the day with 8000 shares at $4.90 per share.
This simple index rises 4.9% over the course of the day.
So ,
[tex]= (5,000 \times \$3.4) + (2,000 \times \$3.20) + (8,000 \times $4.90) * 1.0.49[/tex]
= $70,400
hence, The value of the index at the end of the day should be considered as the $70,400.
Learn more about stock here: https://brainly.com/question/24636535
Hey help me please :) :) :) :) :)
Answer:
2.25
Step-by-step explanation:
2 / (8/9)
Answer:
9/4 or 2 1/4. Hope this helps! The numbers were a bit hard to understand, so if you get it wrong I'm sorry :(
Question 1
4+ (-3) + (-2) ?
Which of the following diagrams correctly represent
Answer:
4-3-2
-1
Step-by-step explanation:
Which function has the same range as | f (x) = negative 2 StartRoot x minus 3 EndRoot + 8?
g (x) = StartRoot x minus 3 EndRoot minus 8
g (x) = StartRoot x minus 3 EndRoot + 8
g (x) = negative StartRoot x + 3 EndRoot + 8
g (x) = negative StartRoot x minus 3 EndRoot minus 8
Answer:
it is c
Step-by-step explanation:
Based on the information given regarding the function, the correct option is C. g (x) = negative StartRoot x + 3 EndRoot + 8.
Interpretation of the function.It should be noted that a function simply means the relation from a set of inputs to a set of possible outputs.
In this case, the function that has the same range as | f (x) = negative 2 StartRoot x minus 3 EndRoot + 8 will be g (x) = negative StartRoot x + 3 EndRoot + 8.
Learn more about functions on:
https://brainly.com/question/10439235
g A zoologist spots what might be a rare subspecies of beetle, due to the pattern on its back. In the rare subspecies, 98% have the pattern. In the common subspecies, 5% have the pattern. The rare subspecies accounts for 1% of the population. Given that a beetle has the pattern, what is the probability that it belongs to the rare subspecies
Answer:
Given that a beetle has the pattern, 0.098 is the probability that it belongs to the rare subspecies
Step-by-step explanation:
Probability of having a pattern in rare subspecies [tex]= 0.98\\[/tex]
Percentage of rare subspecies = 1 % = 0.01
Probability of a beetle with pattern belonging to rare subspecies is
[tex]=0.01 * 0.98 \\= 0.098[/tex]
There are 250 students in a school auditorium.
Complete the table below.
Answer:
first box is 60
second box is 103
third box is 50
last box is 103
Step-by-step explanation:
Help me please and thank you!!!!!
Answer:
D-y=-3x+5
Step-by-step explanation:
Slope is -3x and y intercept is positive 5
Answer:
Step-by-step explanation:
y - 2 = -3(x - 1)
y - 2 = -3x + 3
y = -3x + 5
answer is D
A store pays 70.00$ for a bike the price mark up is 20% what is the mark up amount
Answer:
84$
Step-by-step explanation:
1. 20% of 70
0.20x70 = 14
2. Markup then add
70 + 14 = 84$
Your teacher is giving a 150 point test. There are a total of 46 3-point questions and 5-point questions. How many of each are on the test
Answer:
Let x be the number of 3-point questions.
Let y be the number of 5 point questions.