I'm not 100% sure because it is rare to ask about adding scientific notation but I would answer it like this:
8.4x10^8 +3.7x10^9=
12.1 x 10^17
final answer
Answer:
89
Step-by-step explanation:
There are only 30 pages but last page number is 89.
To find 20% of 950 you would set it up as a proportion. When doing percentages the prevent is always out of 100 so the first step would be 20/100. You are trying to find a number out of 950 so the second part would be ?/950. Now you want to cross multiply and divide. 20*950=19,000 then you divide it by 100 (your other number) 19,000/100=190. So 20% of 950 is 190.