Counting Up Method Parent Reading When using the counting up method, you create a start and end point on your number line. In the case of 321 - 256, the start point is 256 and the end point is 321. The point of counting up is to see what amount is in between these two numbers (the difference) or in other words, you answer the question: "What number plus 256 equals 321?" ( ________ + 256 = 321) Step 1: Make your start and end point of your number line. You are going to try to find nice numbers to hop to from 256 to 321. Step 2: Find a "nice number" to hop to! What's a nice number after 256? 260! How much did I add to get there? 4 Step 3: What's a nice number after 260? 300! And we added 40 to get there. Step 4: Now on to our destination: 321. To get there from 300, all we have to do is add 21. Step 5: Finally, we add our "hops" or "mountains" that got us from 256 to 321. So 4 + 40 + 21 = 65. So we know 321 - 256 = 65 since 256 + 65 = 321. Counting Backward Method Parent Reading When using the counting backward method, you are starting with the amount you have at the beginning and then taking away in parts to get the difference (your mystery endpoint on the number line). In the case of Step 1: Set up your number line. When it comes to counting backward on a number line, you only have a start point. Your end point will be your answer while the hope should total the amount you are subtracting. ' Step 2: We break up the number we're taking away from 74 in this case, 27. We can first take away 20. Counting back from 74, we are now at 54. Step 3: You need to keep track of how much we are taking away. 27-20=7 We can break up 7 by taking away 4 first. Step 4: Finally we take away the remaining 3 to get our answer: 47.
Below are some other ways to solve this problem by counting backwards
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