Answer:
Mean
=Sigma (Number of sleep ×Number of employees) / Sigma Number of employees
= (3×1) + (4×0) + (5×0)+ (6×2)+(7×1)+(8×1) / 1+0+0+2+1+1
= 3+0+0+12+7+8/ 1+0+0+2+1+1
= 30 / 5
= 6
So the mean of number of hour sleep is 6 hours.
I hope this helps
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