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Question
If the total surface area of a solid hemisphere is 462 cm2, then find its volume.
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Solution
As , the total surface area of the solid hemisphere = 462 cm2
⇒ `3pir^2 = 462`
⇒ `3 xx 22/7 xx r^2 = 462`
⇒ `r^2 = (462 xx 7)/(3 xx 22)`
⇒ `r^2 = 49`
⇒ `r^2 = sqrt{49}`
⇒ r = 7 cm
Now, the volume of the solid hemisphere = `2/3 pir^3`
= `2/3 xx 22/7 xx 7 xx 7 xx 7`
= `2156/3` cm3
= `718 2/3 "cm"^3`
= 718.67 `"cm"^3`
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