Find the cubes of 10, 30, 100, 1000. What can we say about the zeros at the end?
Let us first find the cubes and then identify the pattern
103=1000,
303=900×30=27000,
100=10000×100=1000000,
1000=1000000×1000=1000000000
Now, number of zeros in 103 is 3, in 303 is 3, in 1003 is 6, in 10003 is 9.
So, the number of zeros at the end is always a multiple of 3.