Answer:The standard deviation is about 3.6.
Step-by-step explanation:
According to the Range Rule of Thumb : The range is about four times the standard deviation.
i.e. (i)
Given , The race speeds for the top eight cars in a 200-mile race are :
185.9 179.5 189.2 176.7 175.8 188.7. 188.3 177.9
Here , minimum speed = 175.8 and maximum speed = 189.2
Range = maximum speed - minimum speed
i.e. R = 189.2-175.8 =13.4
from (i),
Hence, the standard deviation is about 3.6.