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Mental addition.
Make awkward numbers friendlier. Add in your head, one small step at a time.
YOUR PRACTICE SET10 questions · no timer
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Question 1 of 10No sign-up. No pressure.
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Here’s a way to do it.
48 + 27 = 75
- Split 27 into 20 and 7.
- 48 + 20 = 68.
- 68 + 7 = 75.
Break the second number into tens and ones. Or round 48 up to 50, add 27, then take away the extra 2.
10 questions, plus an answer key on a separate page. For more questions or another level, use the addition worksheets.
Mental addition worksheet
10 questions
NameDateScore/ 10
- 75 + 57 =
- 70 + 23 =
- 27 + 24 =
- 29 + 60 =
- 39 + 47 =
- 39 + 71 =
- 86 + 66 =
- 54 + 17 =
- 60 + 52 =
- 89 + 27 =
iwanttobegoodatmath.com/practice/mental-addition/
Answer key
Mental addition worksheet
- 75 + 57 = 132
- 70 + 23 = 93
- 27 + 24 = 51
- 29 + 60 = 89
- 39 + 47 = 86
- 39 + 71 = 110
- 86 + 66 = 152
- 54 + 17 = 71
- 60 + 52 = 112
- 89 + 27 = 116
iwanttobegoodatmath.com/practice/mental-addition/