Step-by-step explanation:
a. First, find the z-score.
z = (x − μ) / σ
z = (80 − 74.0) / 12.5
z = 0.48
Use a calculator or table to find the probability.
P(z < 0.48) = 0.6844
b. Find the standard deviation of the sample.
σₓ = σ / √n
σₓ = 12.5 / √4
σₓ = 6.25
Find the z-score.
z = (x − μ) / σ
z = (80 − 74.0) / 6.25
z = 0.96
Use a calculator or table to find the probability.
P(z < 0.96) = 0.8315
c. When the distribution of the population is normal, then the distribution of the sample mean is also normal.
Answer: Hello your question is incomplete below is the missing part of the question
The Bureau of the Census reports that the median family income for all families in the United
States during the year 2003 was $43,318. That is, half of all American families had incomes exceeding this amount, and half had incomes equal to or below this amount. Suppose that four families are surveyed and that each one reveals whether its income exceeded $43,318 in 2003.
answer :
P(A) = 11 / 16
P(B) = 3/8
and P(C) = 1/4
Step-by-step explanation:
Making use of the given interpretation for the median we can assign probabilities to simple events as
P(A) = | A | / | sample space |
where | A | = 11
sample space = 16
P(A) = 11 / 16
∴ P(B) = 6/16 = 3/8
and P(C) = 4/16 = 1/4
Answer is: 62.4m^3
The volume of a pyramid is 1/3, where B is the
area of the base and h is the height of the pyramid.
The base of this pyramid is a rectangle with a length
of 8 meters and a width of 4.5 meters. The height of
the pyramid is 5.2 meters.
-10/7
1) -5/7 ➗2/4
2) -5/7 • 4/2
You change the second fraction into a reciprocal, then multiply
The park plans to hire 20 percent more than the minimum number of ticket sellers needed in order to account for sickness, vacation, and lunch breaks. How many ticket sellers should the park hire? Explain.
