Question

Three numbers are in the ratio 3: 4: 5. If the sum of their cubes is 27, then the sum of the numbers is​

Answer 1

Answer:

let three numbers be 3x , 4x and 5x which maintains ratio of 3: 4: 5 , so that ( 3x )3 + ( 4x)3 + ( 5x)3 = 27000 , that is 27x3 + 64x3+ 125x3 = 27000 , so 216x3 = 27000 , therfore x3 = 27000/216 =125 , so x = ( 125)1/3= 5 .Thus the numbers are 3 ( x ) =15 , 4( x ) = 20 and 5( x ) = 25 respectively