# mathematics

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What is the solution for this?
The surface area of a sphere varies in direct proportion to the square of its radius. If a sphere of radius 6cm has a surface area of 452 square cm, find, to the nearest mm, the radius of a spherewith the surface area 1000 square cm.

• mathematics -

36/452 = r^2/1000
r^2 = 36/.452
r = 8.9 cm

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