Answer: 300
We know that 5×3=15. Since we are trying to get 1500 we Multiply 300×5 and get 1500.
How do we know?
- As you can see if you cross out 2 of the 0 in 300 you have 3×5. When you multiply it you get 15.
- Also if you cross out 1 of the 0 in 300 you have 30×5. When you multiply that you get 150.
As you see when you still multiply either of those problems you have 15 in it. So we should know 300×5=1500.
Note: We can also multiply 500×3 and get 1500. You still get the same answer but just switched numbers.