The proportion of Americans who support the death penalty is .53 ...

[olgavictoria]

The proportion of Americans who support the death penalty is .53 . A sample of 1000 randomly selected Americans is surveyed by telephone interview. Use Excel to answer the following questions:
 a. What is the probability that the sample proportion of those supporting the death penalty will be less than .50?
 b. What is the probability that the sample proportion of those supporting the death penalty will be at least .55?
 c. What is the probability that the sample proportion of those supporting the death penalty will be between .50 and .55?
 d. For samples of size 1000, 15 of all sample proportions are at most what value?

Question 2

Given that z is a standard normal random variable, what is the value of z if the area to the left of z is .9382?
 a. 1.8
  b. 1.54
  c. 2.1
  d. 1.77

[ErinKing]

Answer to Question 1

a. .028
=NORM.DIST(0.5,0.53,0.0157,TRUE)
b. .101
=1-NORM.DIST(0.55,0.53,0.0157,TRUE)
c. .871
=NORM.DIST(0.55,0.53,0.0157,TRUE)  NORM.DIST(0.5,0.53,0.0157,TRUE)
d. .514
=NORM.INV(0.15,0.53,0.0157)

Answer to Question 2

b