We need to find
strategies that will help us to solve subtraction problems in different ways.
Here is an example. Problem Jenna decorated 4 cupcakes and her brother decorated 7. How many more cupcakes did he decorate than Jenna? Solution #1 One way to solve this would be to memorize the fact 7 - 4. Solution #2 Another way would be to use a number line to "count back." Begin on the number line at the highest number, 7, then count back, moving your finger or a pencil 4 more numbers. The answer is the number you stop on. You could also use this "count back" method saying the numbers to yourself in your head or out loud. Start at 7. Say 6, 5, 4, 3. Solution #3 Relate addition to subtraction. Try to remember addition facts for 7. Recall the information from the question says one part is 4, so the addition fact 4 + __ = 7 leads you to the answer for the subtraction problem, 7 - 4 = __ These strategies can work for many different problems. Try out a few using each of the strategies and find the one that work best for you.
Click on
the subtraction sign for practice.
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