Posted by tim on Sunday, February 26, 2012 at 9:19pm.
. Each week during the first half of the semester, a sample of 50 students was polled to
determine how many of them had their homework done before class. The following arc
the results of the weekly polls:
Week # # of students with homework done
1 1
2 8
3 12
4 14
5 22
6 30
7 25
8 8
a. Calculate the median.
b. Calculate the standard deviation.

stats  PsyDAG, Tuesday, February 28, 2012 at 12:34am
a. Median is the 50th percentile.
b. Find the mean first = sum of scores/number of scores
Subtract each of the scores from the mean and square each difference. Find the sum of these squares. Divide that by the number of scores to get variance.
Standard deviation = square root of variance
I'll let you do the calculations.