Use the distributive method to check the product
Split 15 into 10 + 5. Multiplying each part by 200 and adding the partial products is a separate, easy-to-audit route to the same answer.
- 1.200 × 10 = 2,000.
- 2.200 × 5 = 1,000.
- 3.2,000 + 1,000 = 3,000.