Question

(6.2 x 10^8) + (2.3 x 10^8)

Answer 1

Using the Order of Operations.
 
(6.2 x 10^8) + (2.3 x 10^8)
(6.2 x 100,000,000) + (2.3 x 100,000,000)
620,000,000 + 230, 000,000
850, 000, 000

Answer 2

(6.2 x 10^8) + (2.3 x 10^8)(620000000) + (230000000)
850000000

Another way to do it is add 6.2 and 2.3
6.2 + 2.3 = 8.5
Then because the exponents are the same, you keep them that way.
8.5 × 10^8

The answer is either 850000000 or (8.5 × 10^8).