Avocet Math video for AMC10 AMC12 preparation
💙 Estimate √2020 by looking to:
40² = 1600
45² ≈ 2020 ??
50² = 2500
and splitting the difference.
±0.1 accuracy is just luck
🤔 Clustered Answer Choices
I didn't make full use of the of the clustered answer choices, 1976.5 ± 2. I was partly guessing if a particular square lied below the median, but we have a reliable estimate of the median, 1976.5 ± 2, so there's no need to guess.
Top AMC problem solvers usually look at the answer choices after reading the question, and I failed to do that here. I remember a tough AMC counting question with answer choices 1, 3, 6, 9, 20. The exact count proved very difficult and time consuming, but one could quickly deduce the count was even and less than ~12 → Answer must be 6. If you ever wonder how the top students get through all 25 AMC questions in 75 minutes, this is how!
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