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Quiz Entry - updated: 2026.07.05

Practice: compute 1,200 − 487 mentally.

713 — count up from 487 to 1,200.

Use the shopkeeper route:

  • 487 → 500 is 13
  • 500 → 1,200 is 700
  • Total jump: 13 + 700 = 713

Counting up is often cleaner than borrowing across zeros.

From Quiz: MENTALMATH / Addition & Subtraction | Updated: Jul 05, 2026