Question

Research suggests that red kangaroos have an average height of 63 in with a standard deviation of 4 in. What is the probability that a random sample of 45 kangaroos has an average of height that is greater than 70 inches.

Answer 1

0.040

Explanation:

We solve using z score

z = (x-μ)/σ,

where x is the raw score = 70 in

μ is the population mean = 63 in

σ is the population standard deviation = 4 in

z = 70 - 63 /4

z = 7/4

= 1.75

Probability value from Z-Table:

P(x<70) = 0.95994

P(x>70) = 1 - P(x<70)

= 0.040059

The probability that a random sample of 45 kangaroos has an average of height that is greater than 70 inches

is 0.040