Q:

To make a glass sphere, 113.04 cm^3 of molten glass is poured into a mold. Using 3.14 for π, Wen finds the circumference of the sphere using the steps below. V=4/3πr^3 113.04=4/3(3.14)r^3 36=4/3r^3 r^3=27 r=9 C=2πr C=18π C=56.52 cm Which statement about Wen’s calculations is true? A. Wen incorrectly calculated the radius. B. Wen did not use the correct formula for the circumference. C. Wen should have used the length of the diameter to find the circumference. D. Wen should have used another formula for the volume.

Accepted Solution

A:
we know that 
[volume of a sphere]=(4/3)*pi*r³
r³=(3/4)*volume/pi------> r³=(3/4)*113.04/3.14----> r³=27
r=∛27----------> r=3 cm

Wen instead of calculating the cubic root of 27 to get the radius, divided 27 between 3 and that's wrong

the circumference C
c=2*pi*r-----> C=2*3.14*3-----> C=18.84 cm

the answer is
A. Wen incorrectly calculated the radius.