SOLUTION: A cone and a pyramid have equal heights and volume. If the base area of the pyramid is 154cm square. Find the radius of the cone. (Take pie = 22/7)

Algebra ->  Probability-and-statistics -> SOLUTION: A cone and a pyramid have equal heights and volume. If the base area of the pyramid is 154cm square. Find the radius of the cone. (Take pie = 22/7)      Log On


   

Question 1163460: A cone and a pyramid have equal heights and volume. If the base area of the pyramid is 154cm square. Find the radius of the cone. (Take pie = 22/7)
Found 2 solutions by Alan3354, greenestamps:
Answer by Alan3354(69443) About Me  (Show Source):
Answer by greenestamps(13203) About Me  (Show Source):
You can put this solution on YOUR website!


If the volumes and the heights are both equal, then the areas of the bases are equal.

The area of the base of the cone is pi%28r%5E2%29; the area of the base of the pyramid is 154 sq cm. So

%2822%2F7%29%28r%5E2%29+=+154
r%5E2+=+154%287%2F22%29+=+7%2A7
r+=+7

ANSWER: The radius of the base of the cone is 7cm.