This year you become a times-tables wizard. You will learn every multiplication fact from 1 × 1 up to 10 × 10. That sounds like a lot — one hundred facts! — but the secret is that there are only really half as many to learn, thanks to a clever trick called commutativity.
What is multiplication?
Multiplication is fast addition of equal groups.
4 baskets, with 6 apples each.
6 + 6 + 6 + 6 = 24.
The short version: 4 × 6 = 24.
Whenever you have equal groups, you can multiply.
The commutative trick
Here is the magic: a × b is the same as b × a.
4 × 6 = 24
6 × 4 = 24
So if you know 4 × 6 = 24, you also know 6 × 4 = 24. That cuts your homework in half!