I need help I found the Exam 1 average 700451 I need help f

I need help.

I found the Exam 1 average = 70.0451

I need help finding the Exam 1 median??

What is the shape of the combined Exam 1 grade distribution?

what is the combined Exam 1 Standard deviation?

Solution

Median should be 73 for Exam1. Because there are 141+103=244 students (244 data values) so median will the average of 122nd and 123rd data value. Since for evening casses mean is 66, and sd is 11.87 so by emprical rule, 99.7% data values lie between 3 standard deviations of mean. So 99.7% data values lie between 30.39 and 101.61. That is both 122nd and 123rd data values of the combined ordered data set are 73. So median for Exam 1 should be 73.

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Since median of the combined data set is greater than mean of combined data set so distribution of Exam1 should be left skewed.

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Standard deviation should be 11.8743 because for morning classes all the data values are same.