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Addition Within 20 — Missing Numbers Worksheet

Missing-addend and missing-sum problems within 20 — equation understanding, not just recall.

1.9+52.+83.7+4.4+15.7+6.3+67.5+38.10+69.+410.5+11.9+12.2+13.10+814.4+15.+716.2+317.+1018.10+19.3+20.10+921.10+722.2+423.+424.+7
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1.9+5142.6+8143.7+3104.4+155.7+10176.3+697.5+388.10+6169.1+4510.5+61111.9+31212.2+1313.10+81814.4+61015.7+71416.2+3517.6+101618.10+31319.3+3620.10+91921.10+71722.2+4623.4+4824.1+78
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Teaching notes

Read every box as 'what goes here?' aloud before starting. A blank in the middle (7 + ▢ = 12) is a genuinely different skill from a blank at the end — expect it to be slower, and grade it that way.

Common Core: 1.OA.D.8

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