1. (3.0x10^4) divided by (6.2x10^1)

= 5x10^2?

2. (4.7x10^-3) divided by (9x10^-4)
= 5x10^-6

3. (3.0x10^4) times (6.2x10^1)
=1.9x10^6

4. (4.7x10^-3) divided by (9x10^-4)
=5x10^-6

5. (5.1x10^2) divided by (3x10^4)

1 answer

1. You're allowed 2 significant figures and you've used only one. So you've rounded too much.
2. exponent is not right.
3. exponnt wrong
4. same as 1? duplicate?
5. no answer.
should be 1.7E-2