A cube of a number is 8 times the cube of another number. If the sum of the cubes of number is 243,then what is difference of the number?

Open in App

Solution

Let the two numbers be a and b. Now a^3 = 8 b^3 = (2b)^3 => a = 2b Also a^3 + b^3 = 243 => 8 b^3 + b^3 = 243 =>9 b^3 = 243 => b^3 = 27 = 3^3 => b = 3 Also we know that a = 2b = 6 Difference = a-b = 6-3 = 3

Suggest Corrections

Similar questions

Prove that if a number is trebled then its cube is 27 times the cube of the given number.

Prove that if a number is tripled , then it's cube is 27 times the cube of the given number

27

Prove that if a number is doubled, then its cube is eight times the cube of the given number.

Join BYJU'S Learning Program