I know that this question had already been answered. But still I could not understand.

Question

I know that this question had already been answered. But still I could not understand. 
Calculate this question and write the answer in standard form.The answer should come 5*10.
(4.5*10^12)divided by (9*10^10)

bobpursley · Answer

4.5E12/9E10= 1/2 E (12-10)=.5E2=5 E 1 or 5*10^1