15,625 multiplied by 1/5 is 3,125.
1,000,000........15625...........x64=========.....1000000
15625
125 x 125 = 15625
15,625 x 125 = 1,953,125
If by "cube of 15625," you mean 156253, then you would multiply 15625*15625*15625. If you have to do this by hand, then first multiply 15625*15625, and then multiply the product of that by 15625 again. Follow the multi-digit multiplication rules, look it up if you don't know them.
1/5 (one fifth)
3 times 25 is 75. 25 times 25 times 25 is 15625.
The number is 1,000,000
one fifteenth
x^6=15625 x=(15625)^(1/6)
The sixth root of 15625, or 15625 ^ (1/6) is equal to 5.
253 = 15625