Answers

2016-03-08T16:58:31+05:30
Since, volume of hollow sphere =4/3×pi×(R^3-r^3)
=4/3×22/7×(8^3-r^3)=11352/7
=88/21×(512-r^3)=11352/7
=512-r^3=11352/7×21/88
=512-r^3=387
=-r^3=387-512=-125
so,r^3=125
therefore r=5.
Now, outer surface area=4×pi×r^2
=4×22/7×8^2
=(88/7×64)cm^2
=5632/7 cm^2
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