measurement (3)

If the sides of a cuboid is increased by 20%. by what percentage does the volume increase?

Let the sides of cuboid be "a" , "b" and "c"

So, volume of cuboid = a x b x c --------------(1)

if the sides are increase by 20%, then the new sides are:

1.2a , 1.2b and 1.2c

So, new volume = 1.2 x a x 1.2 x b  x 1.2 x c = 1.728 abc  ------------(2)

increase = (1.728 - 1) abc

therefore % increase in the volume = 100 x (1.728 - 1)abc/abc = 72.8%

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