Calculating In Standard Form

Question 1

(4.99X10^6)+(1X10^4)

Answer 1

4990000+10000=5000000

5+10^6

Question 2

(2.3 X 10^-2) - (9.1 X 10^-3)

Answer 2

0. 023-0.0091=0.0139

1. 39 X 10^-2

Question 3

(6 X 10^3) X (4 X 10^6)

Answer 3

6 X 4 =24
10^3 X 10^6 = 10^9
24 =2.4 X 10^1
2.4 X 10^1 X 10^9 = 2.4 X 10^10

Question 4

(4.2 X 10^-4)/(7 X 10^2)

Answer 4

4. 2/7= 0.6

0. 6 X (10^-4 X 10^2)=6 X 10^-5