Subtracting 1
🔙 Subtracting 1 is super easy! It's just finding the number that comes right before it.
Do this: Read the concept below, then try the quiz or activity.
Concept
When you subtract 1 from any number, you are just stepping backward one space on the number line.
🎯 The "One Before" Trick: Think about counting. What number comes right before 7? It's 6! So, 7 - 1 = 6.
What comes right before 15? It's 14! So, 15 - 1 = 14.
You don't need fingers or blocks for this trick. Just think about the number that comes right before!
Try it
Let's practice the "One Before" trick!
Instructions: Find the number that comes right before to solve.
Problem 1: 9 - 1 = ? * What number is right before 9? * Answer: ___
Problem 2: 12 - 1 = ? * Answer: ___
Problem 3: 20 - 1 = ? * Answer: ___
Problem 4: 1 - 1 = ? * Answer: ___