Subtraction Sentences Using Number Lines - Up to 20
š¦ Hop backward down the number line! We can use a number line to make subtracting up to 20 super visual and easy.
Do this: Read the concept below, then try the quiz or activity.
Concept
A number line is a straight line with numbers written in order. When we subtract, we hop backward down the line towards zero!
šÆ How to Subtract on a Number Line: Example: 15 - 4 = ? 1. Find your starting point: Put your finger on the big number, 15. 2. Look at the minus number: You need to subtract 4. That means 4 hops backwards. 3. Hop Backward! Hop to the left 4 times: "14... 13... 12... 11". 4. Find your landing spot: You landed on 11! So, 15 - 4 = 11.
Number lines help you see the subtraction happening, instead of just trying to memorize it!
Try it
Let's do some backward hopping!
Instructions: Imagine a number line stretching from 0 up to 20. Count your backward hops.
Problem 1: 18 - 3 = ? * Start at 18. * Hop backward 3 times: "17, 16, 15". * Landing spot: ___
Problem 2: 14 - 5 = ? * Start at 14. * Hop backward 5 times. * Landing spot: ___
Problem 3: 19 - 2 = ? * Answer: ___
Problem 4: You start at 20 and take 6 hops backwards. Where do you land? * Math sentence: 20 - 6 = ___ * Landing spot: ___