Mental strategies, including estimation, to add and subtract whole numbers up to 50
10 tutor-authored questions for this Ontario curriculum expectation, ordered easiest to hardest — every one with a full worked solution. Work through them free, no account needed.
Sample: the first question, solved
Add mentally: 12+15.
📘 Worked solution
✓27.
And one from the hard end
Use a "make ten" strategy to solve 36+7 mentally.
Solution shown after you try it in practice mode.
Work through all 10, easiest to hardest
Your Winny Score tracks you as the questions ramp up. Stuck on one? A real Winny Math tutor will walk you through it — first lesson free.
Start practicing