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Brawn versus brain How is the weight of an animal’s brain related to the weight of its body? Researchers collected data on the brain weight (in grams) and body weight (in Page Number: 813 Page Number: 814 kilograms) for 96species of mammals. The following figure is a scatterplot of the logarithm of brain weight against the logarithm of body weight for all 96species. The least-squares regression line for the transformed data is

logy∧=1.01+0.72logxlogy^=1.01+0.72logx

Based on footprints and some other sketchy evidence, some people believe that a large ape-like animal, called Sasquatch or Bigfoot, lives in the Pacific Northwest. Bigfoot’s weight is estimated to be about 127kilograms (kg). How big do you expect Bigfoot’s brain to be?

Short Answer

Expert verified

The expected brain weight is 334.734grams.

Step by step solution

01

Given Information

Given data:

02

Explanation

Substituting the value of xin the regression equation

logy=1.01+0.72log(127)

=2.5247

Taking each side of the result's exponential with a base of 10:

y=10logy

=102.5247

=334.734

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