The standard deviation of the population of elementary school math- achievement scores is 7.78. A random sample of 20 elementary school children was selected and yielded a mean achievement score of 80.04.
a. Calculate the standard error of the mean.
b. Use the z test to establish whether this sample could be representative of the general population of elementary school children whose mean math achievement score is known to be 78.00.

Question

Quizplus · Accepted Answer

The Answer of The standard deviation of the population of elementary school math- achievement scores is 7.78. A random sample of 20 elementary school children was selected and yielded a mean achievement score of 80.04.
a. Calculate the standard error of the mean.
b. Use the z test to establish whether this sample could be representative of the general population of elementary school children whose mean math achievement score is known to be 78.00.

The Standard Deviation of the Population of Elementary School Math-