The volume of the sphere Q is (37/64)% less than the volume of sphere P and the volume of sphere R is (19/27)% less than that of sphere Q. By what is the surface area of sphere R less than the surface area of sphere P?  Select the correct option:
A) 77.77% B) 75% C) 67.5% D) 87.5% E) None of these
Explanation :   Let the volume of sphere P be 64 parts.   Therefore volume of sphere Q   =&gt;64−(37/64)% of 64.   =&gt;64−37=27 parts.   The volume of R is:-   =&gt;27−(19/27)×27.   =&gt;27−19=8 parts.   Volume ratio:   =&gt;P:Q:R=64:27:8.   Radius ratio:   =&gt;P:Q:R=4:3:2.   The surface area will be 16:9:5.   Surface area of R is less than the surface area of sphere P.   =&gt;16k−4k=12k.   Now,   =&gt;(12k/16k)×100.   =&gt;75%.   Hence, the surface area of sphere R is less than the surface area of sphere P by 75%.   Answer : 75%
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The volume of the sphere Q is (37/64)% less than the volume of sphere P and the volume of sphere R is (19/27)% less than that of sphere Q. By what is the surface area of sphere R less than the surface area of sphere P?