Z = # of SD away from the mean = (x - mean)/SD
Calculate the Z score values for each height. Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportions desired. Multiply that proportion by 1000.
the heights of 1000 students in a college are normally distributed with a mean 5’10" and SD 2". Use 68% for the region from the mean to 1-SD on either side; 94% for the region from the mean to 2-SD on either side and 98% for the region from the mean to 3-SD on either side. Find the approximate number of students in each range of the heights:
28) 5’8"–6’
29) 5’6"–6’2"
30) Above 5’10"
31) Below 6’
32) Above 5’8"
33) 5’8"–6’4"
1 answer
1 answer