EXPRESSING NUMERICAL RESULTS TO CORRECT NUMBER OF SIGNIFICANT FIGURES

a.  Addition and subtraction

The result obtained from adding or subtracting and multiplying or dividing numbers must be quoted based on the number that has the least number of significant figures.

Example 1

Add the following number: 2 345, 7 800 and 934 456.

Solution

The answer is 940 000 and not 944 601 because 7 800 has the least number of significant figures

(which is 2).

Example 2

Work out 2.467 × 465 .

2.7

Solution

424.872222222 to 2 significant figures is 420.