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Year 1 Mental Addition and Subtraction Strategies Worksheet — Level 1 — Practice Set 3 — Answers

Answer sheet with worked solutions for the Year 1 addition worksheet.

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Success TutoringWorksheetsAnswer sheetYear 1 · Mathematics · Addition

Year 1 Mental Addition and Subtraction Strategies Worksheet — Level 1 — Practice Set 3 — Answers

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

1.7 + 8 = 7 + 3 + (answer space) = (answer space)

Answer: 5, 15

  1. 7 + 3 = 10 (a ten)
  2. 10 + 5 = 15
2.9 + 8 = 9 + 1 + (answer space) = (answer space)

Answer: 7, 17

  1. 9 + 1 = 10 (a ten)
  2. 10 + 7 = 17
3.5 + 6 = (answer space) + (answer space) + 1 = (answer space)

Answer: 5, 5, 11

  1. Double 5 is 10
  2. 10 + 1 = 11
4.7 + 9 = 7 + 3 + (answer space) = (answer space)

Answer: 6, 16

  1. 7 + 3 = 10 (a ten)
  2. 10 + 6 = 16
5.8 + 7 = 8 + 2 + (answer space) = (answer space)

Answer: 5, 15

  1. 8 + 2 = 10 (a ten)
  2. 10 + 5 = 15
6.6 + 5 = (answer space) + (answer space) + 1 = (answer space)

Answer: 5, 5, 11

  1. Double 5 is 10
  2. 10 + 1 = 11
7.9 + 4 = 9 + 1 + (answer space) = (answer space)

Answer: 3, 13

  1. 9 + 1 = 10 (a ten)
  2. 10 + 3 = 13
8.9 + 2 = 9 + 1 + (answer space) = (answer space)

Answer: 1, 11

  1. 9 + 1 = 10 (a ten)
  2. 10 + 1 = 11
9.3 + 2 = (answer space) + (answer space) + 1 = (answer space)

Answer: 2, 2, 5

  1. Double 2 is 4
  2. 4 + 1 = 5
10.8 + 3 = 8 + 2 + (answer space) = (answer space)

Answer: 1, 11

  1. 8 + 2 = 10 (a ten)
  2. 10 + 1 = 11
11.6 + 6 = 6 + 4 + (answer space) = (answer space)

Answer: 2, 12

  1. 6 + 4 = 10 (a ten)
  2. 10 + 2 = 12
12.7 + 6 = (answer space) + (answer space) + 1 = (answer space)

Answer: 6, 6, 13

  1. Double 6 is 12
  2. 12 + 1 = 13
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