# Algebra / Scientific Notation

posted by
**Russell**
.

if you have 19.2 x 10 ^ 20 over 4.8 x 10 ^ 9

Would you first subtract 4.8 from 19.2 then subtract 10 ^ 9 from 10 ^20

Leaving an answer of

14.4 x 10^11????

you are using the word "over", which implies division.

Why would you even consider subraction

(19.2 x 10 ^ 20) over (4.8 x 10 ^ 9)

=(19.2 x 10 ^ 20) รท (4.8 x 10 ^ 9)

= 19.2/4.8 * 10^20 / 10^9

= 4 * 10^11

Perhaps you were thinking of the procedure of dividing powers with the same base, where you **subtract** the exponents.

Thank you!!!! My mind is going blah.......first you divide number but then you just subtract then when you divide......this can be confusing, but I get it now :)

Thank you again!