Mistake Detective

Someone's working has a slip in it. Check every line, spot the wrong one and fix it — then pick the right calculation and say what makes sense.

Reasoning & Checking Work · Grades 3–4 · 8 levels · Free

8 levels

  1. Which line is wrong?
  2. Sums that carry
  3. Multiply by parts
  4. Story steps
  5. Which calculation?
  6. Does it make sense?
  7. What should it say?
  8. Every kind of check, timed

What it practises

  • Finding the Mistake
  • Choosing the Calculation
  • Does It Make Sense?

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