Question

If surface area of two cubes are in the ratio 9:1 ,then the ratio of their edges is : *

1 point
81:4
3:1
1:3
4:3

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Answer 1

$\huge\mathbb{\fcolorbox{lime}{lightblue}{ANSWER࿐}}$

$\huge\mathfrak\pink{Given:}$

Surface area of first cube to second cube is 9:1 (in ratio)

$\huge\mathcal\color{yellow}Find:$

Ratio of edges of first cube to second cube.

$\huge\mathcal\orange{Explanation:}$

⇒ Surface area of cube = 6L²

a = first cube area

A = second cube area

⟹$\frac{(6aL²)}{(6AL²)} = \frac{9}{1}$

⟹$\frac{(aL²)}{(AL²)} = \frac{9}{1}$

⟹$\frac{(aL)}{(AL)} = \frac{√9}{√1}$

⟹$\frac{aL}{AL} = \frac{3}{1}$

★ aL = 3 , AL = 1 ★

Ratio of edges of first cube to second cube is 3:1

$\huge\mathfrak\color{lime}I\:hope\:it\:helps\:\:you.$

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