SOLUTION: Suppose 40% of a student population works part time. If a random sample size of 300 students is drawn from the population, then the probability that 44% or fewer of the samples wor
Algebra ->
Probability-and-statistics
-> SOLUTION: Suppose 40% of a student population works part time. If a random sample size of 300 students is drawn from the population, then the probability that 44% or fewer of the samples wor
Log On
Question 1137277: Suppose 40% of a student population works part time. If a random sample size of 300 students is drawn from the population, then the probability that 44% or fewer of the samples work part time is: Answer by rothauserc(4718) (Show Source):
You can put this solution on YOUR website! standard deviation of the sample proportion = square root(0.40 * (1-0.40) / 300) = 0.0283
:
The population proportion is 0.40
:
since the sample size is > 30, we can use the Normal distribution
:
z-score = (0.44 - 0.40) / 0.0283 = 1.4134 is approximately 1.41
:
look in z-table to find the probability corresponding to a z-score of 1.41
:
Probability ( X < 0.44 ) = 0.9207 is approximately 0.92
: