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प्रश्न
Two cubes have their volumes in the ratio 1 : 27. What is the ratio of their surface areas?
उत्तर
The rate of the value of cubes = 1:27
`(a_1^3)/(a_2^2) = 1/27`
`a_1 /a_2 = 1/3` …… (i)
Now,
The ratio of their surface area
`s_1 : s_2 = 6a_1^2 :6a_2^2`
`s_1/s_2 =(6a_1^2)/(6^2)`
`=(a_1/a_2)^2`
`s_1 /s_2 = 1/9`
Hence, `s_1 : s_2 = 1 : 9`
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