Subtract by Counting Back - Up to 20
π£οΈ Time for a countdown! Counting back is the perfect way to quickly subtract small numbers without writing anything down.
Do this: Read the concept below, then try the quiz or activity.
Concept
If you are only subtracting 1, 2, 3, or 4 from a number, the fastest way to solve it is to just count backwards out loud!
π― The "Hold and Tap" Strategy: Example: 17 - 3 = ? 1. Hold the big number: Say "17" out loud to lock it in your brain. 2. Get your fingers ready: Hold up 3 fingers for the number you are taking away. 3. Tap and countdown: Say the numbers backward as you tap your fingers down: "Sixteen, Fifteen, Fourteen." 4. The last number is the answer! So, 17 - 3 = 14.
If you try to count back a big number, like subtracting 12, it takes too long. But for small numbers, it's super fast!
Try it
Blast off with a countdown!
Instructions: Start at the big number and count backward out loud.
Problem 1: 19 - 2 = ? * Hold 19. Count back: "18, ___" * Answer: ___
Problem 2: 15 - 4 = ? * Hold 15. Count back 4 times. * Answer: ___
Problem 3: 13 - 3 = ? * Answer: ___
Problem 4: 20 - 1 = ? * (Just the number that comes right before it!) * Answer: ___