Question

18 x 5 Use mental math to solve. Find as many strategies as you can to solve. Record and describe each strategy.

Answer 1

Answer:

Here are a few ways that I do that:

18 * 5 is the same as (10 + 8) * 5, which equals 50 + 40, which is 90

It's also the same as (20 - 2) * 5, which equals 100 - 10, again, 90

It's also 9 * 2 * 5, which equals 9 * 10, or 90

It's also 3 * 6 * 5, or 3 * 30, which is 90.