statistics
posted by Jennifer on .
For a particular sample of 50 scores on a psychology exam, the following results were obtained.
Mean = 78 Midrange = 72 Third quartile = 94 Mode = 84
Median = 80 Standard deviation = 11 Range = 52 First quartile=68
What score was earned by more students than any other score? Why?
How many students scored between 68 and 94 on the exam?
What was the highest score earned on the exam?
What was the lowest score earned on the exam?

The mode is the most popular grade = 84
68 is the median of the first half
so 25 were between 68 and the median
another 25 were between the median and 94
so
50 students between first quartile 68 and third quartile 94
Mid range is 72.
That is half way between lowest and highest. Range = 52 so high = 72 +52/2 and low = 72 52/2
so
low = 46
high = 98