Estimation Math Example 3

Follow the full solution, then compare it with the other examples linked below.

Example 3

easy
Estimate 39821\frac{398}{21} to the nearest whole number.

Solution

  1. 1
    Round: 398≈400398 \approx 400 and 21≈2021 \approx 20.
  2. 2
    Divide: 40020=20\frac{400}{20} = 20.

Answer

≈20\approx 20
Rounding the dividend and divisor to nearby convenient numbers makes division simple to perform mentally. The exact answer is about 18.9518.95, so our estimate of 20 is reasonable.

About Estimation

Finding a quick approximate answer by rounding to convenient values and computing mentally—no exact calculation needed.

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More Estimation Examples

Example 1 easy

Estimate [formula] without a calculator.

Example 2 medium

Estimate [formula] to the nearest tenth.

Example 4 easy

Estimate [formula] without a calculator.

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