SIGNIFICANT FIGURES

(AKA SIG FIGS)

Sig Figs Significant Figures – the reliable digits in

a measurement based on the precision of the device

In other words, the MORE sig figs it has the more PRECISE the number is

Why are Sig Figs important?

Let’s say I measured the area of the basketball court.Trial 1: Estimate by walking: About

15m wide by 26m long

- Area is about 390m2

Trial 2: Actually measure: 15.24m wide by 25.60m long

- Area is 390.1 m2

Sig Fig Rules

Part 1: Sig Fig Rules Notes How many sig figs do each of the

following numbers have?

Part 1: Sig Fig Rules Group Practice How many sig figs do each of the

following numbers have?

Part 1: Sig Fig Rules Individual Practice

How many sig figs do each of the following numbers have?

Part 2: Rounding to Sig Figs1) Getting rid of extra

sig figs:

Round to the appropriate sig fig

Example: Round 12259 to have

four (4) sig figs

12260

Rounding to Sig Figs2) Need more sig figs:

Add zeroes to the end of the number.

Example: Write 0.23 with four (4)

sig figs

0.2300

Part 2: Rounding Notes Write each of the following numbers with

2 sig figs.

Part 2: Rounding Group Practice Write each of the following numbers with

3 sig figs.

Part 2: Rounding Individual Practice Write each of the following numbers with

3 sig figs.