SOLUTION: Hi! This is what I have given: The ratio of the radius of sphere A to the radius of sphere B is 3:4. I need to find the ratio of the area of sphere A to the area of sphere B.

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Question 1133041: Hi!
This is what I have given: The ratio of the radius of sphere A to the radius of sphere B is 3:4.
I need to find the ratio of the area of sphere A to the area of sphere B.
Thank you so much!

Found 3 solutions by Boreal, Alan3354, greenestamps:
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
The area of a sphere is 4 pi *r^2
therefore the areas of two spheres differ only in the radii here
3^2/4^2 is 9:16
so the ratio of the smaller to larger sphere is 9:16

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
You need to learn this, not keep asking someone to do it for you.

Answer by greenestamps(13200) About Me  (Show Source):
You can put this solution on YOUR website!


It is not necessary to use the formula for the surface area of a sphere to answer this question.

All spheres are similar. For any similar figures, if the ratio of linear measurements between the two is a:b, then the ratio of area measurements between the two is a^2:b^2,and the ratio of volume measurements between the two is a^3:b^3.

In this problem, since the ratio of the radii of the two spheres is 3:4, the ratio of their surface areas is 3^2:4^2 = 9:16.