Answer:
11.2467
Explanation:
First we need to find the mean
Add up all the data and divide by number of points)
(6+7+8+10+12+13+14+17+17+17+18+19+21+23+24+24+25+27+31+31+32+36+36+39+41+45+45+46+49+50)/30
261/10
26.1
Then to find the mean absolute deviation take each value and find the absolute value from the mean and sum it and then divide by the number of points
((26.1 -6)+(26.1-7)+(26.1-8)+(26.1-10)+(26.1-12)+(26.1-13)+(26.1-14)+(26.1-17)+(26.1-17)+(26.1-17)+(26.1-18)+(26.1-19)+(26.1-21)+(26.1-23)+(26.1-24)+(26.1-24)+(26.1-25)+(27-26.1)+(31-26.1)+(31-26.1)+(32-26.1)+(36-26.1)+(36-26.1)+(39-26.1)+(41-26.1)+(45-26.1)+(45-26.1)+(46-26.1)+(49-26.1)+(50-26.1))/30
11.2467