how would I write this in scientific notation 04980000007507

I am getting confused with it all can you help me fine examples with this. thanks
also
how would I add this up 10^4+10^4+10^3=
is it 21000 or 10^11

Is there a type somewhere?

Usually we don't write leading zeroes of whole numbers like you did in 04980000007507

Furthermore, whether your number is a whole number or a decimal, the 7507 part at the end becomes rather "insignificant".

How many decimal places should your answer contain?

As to your question 10^4+10^4+10^3
we cannot add powers with different exponents.
In this case evaluate each one.
so
10^4+10^4+10^3
= 10000 + 10000 + 1000 = 21000
(certainly not 10^11, which would be
100000000000 )