Question

What is the sum of 2.5 × 10^4 and 3.4 × 10^4?

0.59 × 10^4
0.59 × 10^8
5.9 × 10^4
5.9 × 10^8

Answer 1

Here, you'd combine like terms. 
2.5 + 3.4 = 5.9
10^4 + 10^4 = 10^8

5.9 x 10^8