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1st Grade Mental Addition and Subtraction Strategies Worksheet — Level 1 — Practice Set 2 — Answers

Answer sheet with worked solutions for the 1st Grade addition worksheet.

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Success TutoringWorksheetsAnswer sheet1st Grade · Mathematics · Addition

1st Grade Mental Addition and Subtraction Strategies Worksheet — Level 1 — Practice Set 2 — Answers

Fill in each step of the strategy, then write the answer.

1.7 + 4 = 7 + 3 + (answer space) = (answer space)

Answer: 1, 11

  1. 7 + 3 = 10 (a ten)
  2. 10 + 1 = 11
2.9 + 4 = 9 + 1 + (answer space) = (answer space)

Answer: 3, 13

  1. 9 + 1 = 10 (a ten)
  2. 10 + 3 = 13
3.2 + 3 = (answer space) + (answer space) + 1 = (answer space)

Answer: 2, 2, 5

  1. Double 2 is 4
  2. 4 + 1 = 5
4.6 + 9 = 6 + 4 + (answer space) = (answer space)

Answer: 5, 15

  1. 6 + 4 = 10 (a ten)
  2. 10 + 5 = 15
5.8 + 3 = 8 + 2 + (answer space) = (answer space)

Answer: 1, 11

  1. 8 + 2 = 10 (a ten)
  2. 10 + 1 = 11
6.3 + 2 = (answer space) + (answer space) + 1 = (answer space)

Answer: 2, 2, 5

  1. Double 2 is 4
  2. 4 + 1 = 5
7.9 + 9 = 9 + 1 + (answer space) = (answer space)

Answer: 8, 18

  1. 9 + 1 = 10 (a ten)
  2. 10 + 8 = 18
8.7 + 8 = 7 + 3 + (answer space) = (answer space)

Answer: 5, 15

  1. 7 + 3 = 10 (a ten)
  2. 10 + 5 = 15
9.8 + 7 = (answer space) + (answer space) + 1 = (answer space)

Answer: 7, 7, 15

  1. Double 7 is 14
  2. 14 + 1 = 15
10.8 + 7 = 8 + 2 + (answer space) = (answer space)

Answer: 5, 15

  1. 8 + 2 = 10 (a ten)
  2. 10 + 5 = 15
11.8 + 4 = 8 + 2 + (answer space) = (answer space)

Answer: 2, 12

  1. 8 + 2 = 10 (a ten)
  2. 10 + 2 = 12
12.8 + 9 = (answer space) + (answer space) + 1 = (answer space)

Answer: 8, 8, 17

  1. Double 8 is 16
  2. 16 + 1 = 17
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