Answer:
The standard deviation is 22.6 to the nearest tenth
Step-by-step explanation:
* Lets study how to find the standard deviation (σ) for data set
- First step find the mean of the data
∵ The mean = the sum of the data ÷ the number of the data
# The sum of the data is
359 + 320 + 365 + 310 + 349 + 351 + 310 + 314 + 364 = 3042
# The number of the data is 9
∴ The mean = 3042 ÷ 9 = 338
- Second step find the difference between each data and the mean
and square the difference
# 359 - 338 = 21 ⇒ (21)² = 441
# 320 - 338 = -18 ⇒ (-18)² = 324
# 365 - 338 = 27 ⇒ (27)² = 729
# 310 - 338 = -28 ⇒ (-28)² = 784
# 349 - 338 = 11 ⇒ (11)² = 121
# 351 - 338 = 13 ⇒ (13)² = 169
# 310 - 338 = -28 ⇒ (-28)² = 784
# 314 - 338 = -24 ⇒ (-24)² = 576
# 364 - 338 = 26 ⇒ (26)² = 676
- Third step find the variance (σ²)
# Add all the square difference and divide the sum by the
number of data
∴ σ² = (441 + 324 + 729 + 784 + 121 + 169 + 784 + 576 + 676) ÷ 9
∴ σ² = 4604 ÷ 9 = 511.5555556
- Fourth step find the standard deviation σ it is the square root of
the variance
∴ σ = 22.6 to the nearest tenth
* The standard deviation is 22.6 to the nearest tenth
