What do you notice? Why did does this happen

Answer:
The thing you should notice is that when we multiply a number by 10^n
(where n is the number of zeros that the number has) we move the decimal point on the first number n times to the right.
For example, if we have the number:
7.231 and we multiply it by 100 (there are 2 zeros) then the decimal point is moved two times to the right:
7.231*100 = 723.1
This happens because the base of our math is 10 (the decimal system).