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 Tweet # Significant Figures

Introduction: In athletic events, especially events like the Olympics, it is necessary to report measurements and times to as many figures as possible, since the times between athletes tend to be very close. If there is to be a true winner chosen, therefore, 48.8141 seconds is more valid and reliable than 48.81 seconds. This is how it has been determined that various athletes have maintained their titles and that, in some cases, they have maintained endorsements from various organizations and celebrity statuses.

Significant figures relate to the notion of reporting measurements and results of calculations to a certain number of figures. Significant figures fall under the following criteria: (1) all nonzero digits; (2) zeroes between significant figures; and (3) trailing zeroes to the right of a decimal point. On the other hand, trailing zeroes to the left of a decimal point and leading zeroes to the right a decimal point tend not to be significant. Determining which digits are significant is important they help to describe how accurate a measurement is.

Significant figures are also applied to the operations of addition, subtraction, multiplication, and division after the answer is found. In problems involving addition and subtraction, only the decimal places of the numbers are considered, with the answer expressed to the least number of decimal places in any part of the problem. For example, 9.3 - 1.03 would be expressed as 8.3, since there is only one decimal place in 9.3. In problems involving multiplication and division, on the other hand, the answer is expressed to the least number of significant figures possible. For example, 2.9 x 3.17 would be expressed as 9.2, since there are only two significant figures in 2.9.

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