Practice: Read the ruler measurement to the correct number of significant figures.

**Significant figures** are necessary to communicate the level of accuracy with which values are recorded.

Concept #1: To determine the number of significant figures for a value is dependent on the presence of a demical point.

Example #1: How many sig figs does each number contain?

**(1)** 0.0001010 m **(2) **10030 s

**(3)** 2.00 x 10** ^{3}** m

● Multiplication/Division: Measurement with least ** SIG FIGS** determines final answer.

● Addition/Subtraction: Measurement with least ** DECIMAL PLACES** determines final answer.

Example #2: Perform the following calculations to the right number of sig figs:

[(0.999 + 1.01) ● (15.1 - 0.815)] / (0.010)(16) + (33.3 + 7.5)

Example #3: Read the water level with the correct number of significant figures.

A) 6.80 mL B) 7 mL C) 7.0 mL D) 7.00 mL E) 7.20 mL

Practice: Read the ruler measurement to the correct number of significant figures.

Practice: Read the ruler measurement to the correct number of significant figures.