One way is to factor and group and get every 3 729=3 times 3 times 3 times 3 times 3 times 3 so we group the ones that happen 3 times 729=(3*3*3) times (3*3*3) we know that we can take the cube root of each group and multiply the result 729==(3)(3)=9
A + B + C = 518 ft^3 A = 1/3B, or 3A = B B = C A + B + C = 518 ft^3 1/3B + B + B = 518 7/3B = 518 B = 518×3/7 = 222 ft^3 A = 1/3B = 1/3×222 = 74 ft^3 C = B = 222 ft^3
