Mental strategies, including estimation, to add and subtract whole numbers up to 50
30 tutor-authored questions for this Ontario curriculum expectation, ordered easiest to hardest, every one with a full worked solution. Work through all 30, included free with your weekly lessons.
Sample: the first question, solved
Add mentally: 12+15.
📘 Worked solution
✓27.
And one from the hard end
Two mental strategies for solving 38+27 both give the same answer. Which pair of steps is correct?
Solution shown after you try it in practice mode.
Work through all 30, easiest to hardest
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