Answer:
Standard deviation = 2.569
Step-by-step explanation:
The mean = (10 + 15 + 8 + 16 + 14 + 12 + 9 + 12 + 14 + 10) ÷ 10 = 12
x - mean = -2 , 3 , -4 , 4 , 2 , 0 , -3 , 0 , 2 , -2
(x - mean)² = 4 , 9 , 16 , 16 , 4 , 0 , 9 , 0 , 4 , 4
Σ(x - mean)² = 4 + 9 + 16 + 16 + 4 + 0 + 9 + 0 + 4 + 4 = 66
Standard deviation = √(66/10) = 2.569
