Addition of Mass and conversion to grams

Question

We have the following masses: 20,000,000 kg; 5,000 dg; 650mg. What is the total mass in grams?

Answer 1

2x10⁷ kg x 1x10³ g/kg = 2x10¹⁰ g

5x10³ dg x 1x10^-1g/dg = 5x10² g

650 mg x 1 g/1000 mg = 0.65 g

Add them together and report answer to 2 decimal places