The average value is the median value of each group of frequencies multiplied by the frequencies and then added.

Average value = 4 (3 * 0.027 * 0.0811* 0.0917 * 0.03) = 8.48.

Variance =1/5 [(3-8.48) 2 (7-8.48) 2 (11-8.48) 2 (15-8.48) 2 (/9)

The median value is a value corresponding to half the area of the frequency distribution histogram.

That is, the sum of the left and right areas is 0.5. Let the median be 9 x.

Then 4*(0.02 0.08 x)=0.5 x=0.025, so the median is 9.025.

This mode is the intermediate value with the highest frequency.

Yes 1 1.