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The diameter of one side of a 10-foot log is approximately 13 inches. The diameter of the other side of the log is approximately 11 inches. Which is the best way to estimate the volume in cubic feet of the log?

The diameter of one side of a 10-foot log is approximately 13 inches. The diameter-example-1
User Dercni
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2 Answers

1 vote
Find the average of the areas of the ends. Then take it times the length of the log in inches
User Pbond
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Answer with explanation:

As, the log is in the shape of Frustum.We will use the Formula of frustum to find the volume.

A=13 inches,B=11 inches, H=10 feet

Volume of Frustum


=(\pi* H)/(3)[A^2+B^2+AB]\\\\=(3.14 * 10)/(3)*[((13)/(2))^2+((11)/(2))^2+(13)/(2) * (11)/(2)]\\\\=(31.4)/(3) * [(169)/(4)+(121)/(4)+(143)/(4)]\\\\=(31.4)/(3) * (433)/(4)\\\\=1133

Ok, when you will round up the numbers, in equation of Volume it will give

Volume of frustum = 3 × 36 × 10 cubic feet(Approximate)

Because ,


\rightarrow(3.14 * 10)/(3)=10\\\\\rightarrow (169)/(4)+(121)/(4)+(143)/(4)=36 * 10

Option C:

User Shezad
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