2-min Fluency Warm-up — Facts you already know!
5 × 4 =
3 × 6 =
2 × 8 =
4 × 5 =
5 × 7 =
3 × 9 =
The Turn-Around Trick! When you flip the numbers, the answer stays the same. 6 × 3 = 3 × 6. Look — it's the same array, just turned!
3 rows of 6
3 × 6 =
6 rows of 3
6 × 3 =
So if you know your 0-5 facts, you ALREADY know most 6-10 facts!
Flip each hard fact into an easy fact you already know, then solve.
7 × 2 → flip it: ×
Answer:
8 × 5 → flip it: ×
Answer:
9 × 3 → flip it: ×
Answer:
6 × 4 → flip it: ×
Answer:
Number Talk — Explain WITHOUT calculating.
Kim knows 5 × 8 = 40 but is stuck on 8 × 5.
What would you tell Kim?
My thinking:
Does the turn-around trick work for SUBTRACTION? Is 8 − 5 the same as 5 − 8?
My thinking:
Challenge
Draw two arrays that prove 4 × 7 = 7 × 4 in the space below.
Write two more turn-around pairs of your own: and