Q15 of 45 Page 7

Three numbers are in the ratio 1:2:3. The sum of their cubes is 98784. Find the numbers.

Let the numbers are = x, 2x and 3x


According to the question,

x3 + (2x)3 + (3x)3 = 98784

x3 + 8x3 + 27x3 = 98784

36x3 = 98784


So, the numbers are ,


x = 14


2x = 2 × 14 = 28


3x = 3 × 14 = 42

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