#1**+1 **

Multiplying a number by 10 moves the decimal point to the right one place.

For example... 2 * 10 = 20 and 0.7 * 10 = 7

When we multiply 2.56 by 1,000,000,000 , we are multiplying 2.56 by 10 , *9 times*.

So we need to move the decimal point to the right 9 places.

2.56 * 1,000,000,000 = 2,560,000,000.0

The decimal point goes at the very end of 2,560,000,000 , but it isn't necessary to write it since only zeros follow it.

hectictar Oct 13, 2017