Saturday, August 14, 2010

August 2010 Brainteaser Solution

Determine the smallest integral (whole number) value of x that will make the product 4840x a perfect cube.

Thefactors of 4840 = 484 x 10 = 22 x 22 x 10 = 2 x 11 x 2 x 11 x 2 x 5 (the prime factors)

To make a perfect cube, you need three of each factor:

you have enough 2s, so you need 2 5's and one 11.

5 x 5 x 11 = 275