Question

The mean height of women in a country​ (ages

20minus−​29)

is

63.6

inches. A random sample of

65

women in this age group is selected. What is the probability that the mean height for the sample is greater than

6464

​inches? Assume

sigmaσequals=2.87.

The probability that the mean height for the sample is greater than 64 inches

​(Round to four decimal places as​ needed.)

Answer 1

Solution :

Given that ,

mean = = 63.6

standard deviation = = 2.87

n = 65

= 63.6

= / n = 2.87 / 65= 0.36

P( > 64) = 1 - P( <64 )

= 1 - P[( - ) / < (64-63.6) /0.36 ]

= 1 - P(z <1.11 )

Using z table

= 1 - 0.8665

= 0.1335

probability= 0.1335