@selenabui3579: Estimate 198 × 21 in 3 seconds! 💡 Round each number: 198 → 200, 21 → 20. 200 × 20 = 4,000 ✅ Why it works: you barely moved the numbers, so the exact answer 4,158 is within 4%! Save this for mental math practice 📚 #Estimation #MentalMath #MathHelp #LearnMath

Selena Bui

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Thursday 15 October 2026 19:17:26 GMT