Welcome to Math 6

Ratios and Conversion

Factors

The Connector…

We have already explored what ratios are and used them to solve different types of problems.

Today’s lesson is an extension of what we have learned about ratios.

KEY VOCABULARYA conversion factor is a ratio written in fraction form that can express the same value or quantity in two different units.

1124

241

dayhours

hoursday

OBJECTIVE:

Each student will:Use a conversion factor to change

from one unit to another.Use conversion factors to solve

problems.

http://www.wsdot.wa.gov/Reference/metrics/factors.htm#length

WEBSITE

To convert from

to multiply by

miles (US Statute)

kilometer (km) 1.609347

inch (in) millimeter (mm) 25.4 *inch (in) centimeter (cm) 2.54 *

inch (in) meter (m) 0.0254 *foot (ft) meter (m) 0.3048 *yard (yd) meter (m) 0.9144 *

Length Conversion Factors

To convert from

to multiply by

pound (lb) kilogram (kg) 0.4535924

ton, 2000 lb kilogram (kg) 907.1848

Mass Conversion Factors

Mass (weight)

mile km 1.609347

yard m 0.9144**

foot m 0.3048**

inch mm 25.40**

To convert

From English Units

To Metric Units

Multiply by*

Other Useful Conversion Factors

Guided Practice

Guided PracticeProblems with a single conversion

factor.

How many cm are in 18.7 inches?

in

cmin

1

54.27.18

Guided PracticeProblems with two or more

conversion factors.

How many grams are in 0.143 ounces?

gramsoz

gramoz 05.4

03527.0

1143.0

Guided Practice

A typical hospital IV bag contains 1000 cc’s. Will this volume fit inside a ½ gallon milk jug?

1 cc = 1 cm3 = 1 mL

1000mL= 1 Liter

1 gallon = 3.785 Liters

Conclusion:

Conversion factors are used to solve science problems and every day life problems.

Assignments

1- Conversion Factor Practice. Worksheet.

Final thought…

Learning new things in Math, as in any subject, can sometimes take lots of practice. But you will eventually succeed if you have patience.

Some things will come easily, some things may not. You definitely will need persistence along the way.