The brain volumes (cm cubed) of 50 brains vary from a low of 902 cm cubed to a high of 1494 cm cubed. Use the range rule of thumb to estimate the standard deviation s and compare the result to the exact standard deviation of 183.2 cm cubed, assuming the estimate is accurate if it is within 15 cm cubed.

A) Estimated standard deviation = 148cm³

B) The estimated standard deviation of 148 cm³ is less than the true standard deviation of 183.2 cm³. This estimated standard deviation is not even within 15 cm³ of the true standard deviation and thus we can say it's not accurate.

Step-by-step explanation:

From the question, the given standard deviation is 183.2 cm³

Also that the range of values is between 902 cm³ to 1494 cm³.

Range is the difference between highest and lowest values in the data set.

Thus, Range = 1494 cm³ - 902 cm³ = 592 cm³

Now, The range rule tells us that the standard deviation of a sample is approximately equal to one-fourth of the range of the data. In other words s = (Maximum – Minimum)/4

Thus, estimated standard deviation = 592/4 = 148 cm³

c) the median for town a 30" is greater than the median for town b 25"

step-by-step explanation:

town a, median = q2 = 30

town b, median - q2 = 25

so the median for town a 30" is greater than the median for town b 25"