In: Statistics and Probability
The average GPA at a college is 2.73 with a standard deviation of 0.8. Find the probability that 10 randomly selected students will have an average GPA greater than 2.37
Solution :
Given that ,
mean = = 2.73
standard deviation = = 0.8
n = 10
= 2.73
= / n = 0.8 / 10 = 0.2530
P( >2.37 ) = 1 - P( <2.37 )
= 1 - P[( - ) / < (2.37 -2.73) /0.2530 ]
= 1 - P(z < -1.42)
Using z table
= 1 - 0.0778
= 0.9222
probability= 0.9222