Lesson 11-7 Pages 590-594

Precision and Significant Digits

What you will learn!1. How to describe the

measurements using precision and significant digits.

2. How to apply precision and significant digits in problem-solving situations.

PrecisionPrecisionSignificant digits Significant digits

What you really need to know!

The precision of a measurement is the exactness to which a measurement is made.

What you really need to know!

Significant digits indicate the precision of the measurement.

What you really need to know!If a number contains a decimal point, the number of significant digits is found by counting the digits from left to right, starting with the first nonzero digit and ending with the last digit.

What you really need to know!If a number does not contain a decimal point, the number of significant digits is found by counting the digits from left to right, starting with the first digit and ending with last nonzero digit.

What you really need to know!When adding or subtracting measurements, the sum or difference should have the same precision as the least precise measurement.

What you really need to know!When multiplying or dividing measurements, the product or quotient should have the same number of significant digits as the measurement with the least significant digits.

Link to Pre-Made Lesson

Example 1:

Identify the precision unit of the thermometer shown:

5°F

Example 2:

Determine the number of significant digits in the measure.

MeasurementMeasurement Significant digitsSignificant digits

1,040 miles1,040 miles 330.003 cm0.003 cm 1190.051 kg90.051 kg 55

0.06300 Liter0.06300 Liter 44

Example 3:

The sides of a quadrilateral measure 0.6m, 0.044m, 0.24m, and 0.103m. Use the correct number of significant digits to find the perimeter.

0.60.6 110.0440.044 220.0240.024 220.1030.103 330.7710.771 PerimeterPerimeter0.8 m0.8 m 11

Example 4:

A room is 12.25 ft wide and 14 ft long. What is the area of the room?

Example 4:

A room is 12.25 ft wide and 14 ft long. What is the area of the room?

12.2512.25 441414 22171.5171.5 AreaArea170 ft170 ft22 22

Page 592

Guided Practice

#’s 4-12

Pages 590-592 with someone at home and

study examples!

Read:

Homework: Pages 593-594

#’s 13-38 all

#’s 41-47

Study Guide and Review

Pages

595-598

#’s 1-32(Odd answers in back of book)

Prepare for Test!

Page

599

#’s 1-20

Prepare for Test!

Pages

600-601

#’s 1-20

Page

752

Lesson 11-7