Question

A simple random sample of size n=49 is obtained from a population with µ=83 and σ=21.
Describe the sampling distribution of x̄, is this distribution approximately normal. (enter Yes or No)

What is P(x̄>88.1)=

Answer 1

Solution :

Given that,

mean = = 83

standard deviation = = 21

= =83

= / n = 21/ 49 = 3

sampling distribution of x̄, is this distribution approximately normal. YES

P(x̄>88.1)== 1 - P( <88.1 )

= 1 - P[( - ) / < (88.1-83) /3 ]

= 1 - P(z <1.7 )

Using z table

= 1 - 0.9554

= 0.0446

probability= 0.0446