Subtracting 1

Learning Objectives Subtract 1 from any number between 1 and 20. Identify the number that comes just before a given number. Use objects like blocks or toys to show subtracting 1. Write a complete subtraction sentence for taking away 1. Solve simple word problems that involve subtracting 1. Explain that subtracting 1 is the same as counting back one step. You have 5 yummy cookies 🍪. If you eat one, how many are left? Today, we will learn a super easy trick! We will learn how to subtract 1. It's just like finding the number that came before! Real-World Applications Eating one grape from a bunch 🍇 Giving one toy to a friend 🧸 One bird flying away from a tree 🐦 Spending one dollar at the store 💵

TermDefinitionExample SubtractTo take away or make a number smaller. It means you have less.If you have 4 balls ⚽⚽⚽⚽ and you subtract 1, you have 3 balls left. Minus Sign (-)This little line tells us to subtract. It looks like this: -We read '5 - 1' as 'five minus one'. Equals Sign (=)This sign means 'is the same as'. It shows us the answer.In '3 - 1 = 2', the equals sign tells us the answer is 2. DifferenceThe answer you get when you subtract two numbers.For 8 - 1 = 7, the difference is 7. Number BeforeThe number that comes right before another number when you count.The number before 6 is 5. So, 6 - 1 = 5.

The 'One Less' Rule n - 1 = the number right before n When you subtract 1, the answer is always the number that comes just before. The 'Counting Back' Rule n - 1 is the same as counting back one step Start at your number and say the next number as you count backwards. The 'Anything Minus Itself' Rule 1 - 1 = 0 If you have one of something and you take that one away, you have zero left.