Estimation means finding an approximate answer to a calculation. Estimating involves rounding numbers to 1 or 2 significant figures before performing a calculation. The estimated answer would be close to the actual answer.
Estimation in calculations
Round the numbers in the calculation to 1 or 2 significant figures before performing the calculation to find an approximate answer.
Example 1
Estimate the value of14.467.9+2.16.
First, round all 3 numbers to an appropriate number of significant figures:
67.9↦68
2.16↦2
14.4↦14
Carry out the calculation with the rounded numbers:
14.467.9+2.16≈1468+2=1470=5
14.467.9+2.16≈5
Estimation with square roots
Square roots can be estimated by identifying square numbers near a number.