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Curriculum › Math ›Grade 2

Grade 2 Math · Level 4, Arithmetic within 100

Addition With a Missing Number

Find an unknown number in an addition equation by understanding how the quantities relate.

Questions like

  • 38 + __ = 57

How the lesson starts: Addition With a Missing Number

  1. Theo's magic hat

    Ta-da! Magician Theo has 8 bunnies. Some more bunnies hop out of his hat. Now there are 15! How many hopped out? Let's find the missing number!

  2. Count on

    Start at 8. Hop 2 to get to 10. Then hop 5 to get to 15. 2 + 5 = 7. So 7 bunnies hopped out! Check: 8 + 7 = 15.

  3. Hop to ten

    Try 7 + blank = 16. Start at 7. Hop 3 to get to 10. Then hop 6 to get to 16. 3 + 6 = 9. So the blank is 9. Check: 7 + 9 = 16!