Estimating calculations - 5th Sep 2008

The first part of Module 3 chapter 2 is concerned with estimating answers to calculations by rounding the numbers to one significant figure (1sf).

If you are not sure how to round to significant figures you can look at the Mymaths lesson on the topic.

Example:

Estimate the answer to 3.86 x 2.14

3.86 is 4 to 1sf and 2.14 is 2 to 1sf

so 3.86 x 2.14 ≈ 4 x 2 = 8

It is difficult to calculate with decimals so it is a good idea to estimate answers to calculations using this method to help you check that you are correct if you do the exact calculation.

There is a Mymaths lesson on estimating calculations that covers the work from this lesson and the next couple of lessons.