A sample of size 70 will be drawn from a population with mean 24 and standard deviation 10. Find the probability that will be between 22 and 25.
a. .0475
b. .2005
c. .7516
d. .7326
A sample of size 42 will be drawn from a population with mean 34 and standard deviation 8. Find the probability that will be greater than 36.
a. .0351
b. .0749
c. .9474
d. .0525
A certain car model has a mean gas mileage of 29 miles per gallon (mpg) with a standard deviation of 5 mpg. A pizza delivery company buys 38 of these cars. What is the probability that the average mileage of the fleet is greater thatn 27.8 mpg?
a. .9535
b. .8599
c. .9305
d. .0465
The mean number of pets per hosehold is 3.25 with standard deviation 1.3. A sample of 59 households is drawn. Find the 74th percentile of the sample mean.
a. 4.11
b. 3.36
c. 3.86
d. 2.70
The mean annual income for people in a certain city (in thousands of dollars) is 42, with a standard deviation of 38. A pollster draws a sample of 40 people to interview. What is the probability that the sample mean income is less than 35 (thousands of dollars)?
a. .0934
b. .8554
c. .1446
d. .1220
The mean annual income for people in a certain city (in thousands of dollars) is 38, with a standard deviation of 31. A pollster draws a sample of 43 people to interview. Find the 68th percentile of the sample mean.
a. 38.7 thousand dollars
b. 40.2 thousand dollars
c. 42.3 thousand dollars
d. 37.7 thousand dollars