# Significant Figures

Topics: Significant figures, Arithmetic, Measurement Pages: 4 (968 words) Published: June 10, 2012
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When we use an equipment to take measurement, it is important to be honest when reporting a measurement, so that it does not appear to be more accurate than the equipment used to make the measurement allows. To achieve this, we can control the number of significant figures used to report the measurement.

When we look at a number, its first significant figure is the first digit from the left, other than 0. E.g. -in the number 539 the first significant figure is 5
-in the number 0.06189 the first significant figure is 6

The number of significant figures is the number of digits counting from the left from the first significant figures.

By looking at the examples below, generate some rules in determining the number of significant figure of a number. * in the number 0.06189 there are four significant figures * in the number 2390001 there are seven significant figures * in the number 2390000 there are three (or seven) significant figures** * in the number 2390000.00 there are nine significant figures

The rules that I can generate are:

When using calculator to solve a problem, the answer shown on the calculator may consist of many digits. But not all the numbers that appear on the calculator are ‘significant’. You may just want to express your answers in, for example, three significant figures.

The examples below show how you should express your answer in 3 significant figures. Fill in the blanks. * 981.2645 should be written as 981
* 2.365789 should be written as 2.37
* 4321789.1 should be written as 4320000
* 7.1000000 should be written as __________
* 3629.3309 should be written as __________
* 0.0056793 should be written as __________

Self directed learning:
Take the quiz to test your understanding on significant figure:...