Scores on a national writing exam are approximately normally distributed, with a mean of 490 and a standard deviation of 20. Consider random samples of size 25 from the population of test takers.
describe the sampling distribution of a sample mean.
shape
mean=
standard deviation=
find the probability that a random sample of 25 test takers will have a mean exam score that is greater than 496
find k such that p(x<K)=.01
2 answers