Post on 06-Jan-2016
description
Using the Conversion Factor
Objective: Make unit conversions
Fill in the Missing Numbers
1 foot = _____ inches
1 meter = _____ centimeters
1 pound = _______ ounces
1 minute = ______ seconds
1 hour = ________ minutes
1 day = __________ seconds
12
100
16
60
60
86,400
Unit conversion factorA unit conversion factor is a fraction whose numerator and denominator are equivalent measures. Some common unit conversion factors are given below. You can also use the reciprocal of these.
1 ft? in.
1 yd? ft
1 mi? ft
1lb? oz
1 pt? c
1 qt? pt
1 gal? qt
1 hr? min
1 min? s
1m? cm
1km? m
Unit conversion factorA unit conversion factor is a fraction whose numerator and denominator are equivalent measures. Some common unit conversion factors are given below. You can also use the reciprocal of these.
Choose a unit conversion factor that…
• Introduces the unit you want in the answer
• Cancels out the original unit so that the one you want is all that is left.
“Canceling” out Words
inches feet
feet miles
seconds hours
minutes seconds
inches
miles
hours
minutes
Practice: Choose the appropriate conversion factor.
Inches to feet 1 ft
12 in.12 in.
1 ft
Minutes to hours60 min
1 hr
1 hr
60 min
Meters to centimeters 1 m
100 cm
100 cm
1 m
inches
1
minutes
1
meters
1
Convert 8 yards to feet…
Make a decision: What conversion factor will you use?
3 ft 1 yd or
1 yd 3 ft
Hint!Use the one that will cancel out the units you want to change
Set up the problem: Multiply the measurement by the conversion factor.
ft yd
1 yd
38
Solve the problem: Perform the multiplication
ft yd ft ft yd ft
1 yd 1 yd
3 8 3 248 24
1 1
8 yards
1
A bucket holds 16 quarts. How many gallons of water will fill the bucket? Use a unit conversion factor to convert the units.
What are the two conversion factors comparing quarts and gallons?
4 qt
1 gal
1 gal
4 qt
Which one will “cancel” quarts?
16 qt 16 gal 4 gal
4
You Try it!One bag of apples weighs 64 ounces. How many pounds does it weigh?
1 lb 64 1 lb64 oz = 4 lb
16 oz 16
Darren drank 2 liters of water. How many milliliters of water did he drink?
1000 mL 2 1000 mL2 L = 2000 mL
1 L 1 L
Making Rate Conversions
Use a unit conversion to convert the units within each rate
Convert 80 miles per hour to feet per hour.
80 mi
1 hr
5,280 ft
1 mi
80 5280 ft
1 hr
422,400 ft
1 hr
Convert 63,360 feet per hour to miles per hour.
63,360 ft
1 hr
1 mi
5280 ft 63,360 ft 1 mi
1 hr 5280 ft
12 mi
1 hr
You Try it!Convert 32 feet per second to inches per second.
32 ft 12 in 32 ft 12 in 384 ft =
1 s 1 ft 1 s 1 ft 1 s
A craft store charges $1.75 per foot for lace. How much per yard is this?
$1.75 3 ft $1.75 3 ft $5.25 =
1 ft 1 yd 1 ft 1 yd 1 yd
Word Problems
The average American eats 23 pounds of pizza per year. Find the number of ounces the average American eats per year.
23 lb 16 oz 23 16 368 oz
1 yr 1 lb 1 1 yr
The average American eats 368 ounces of pizza per year.
General Math click here
Pre-Algebra click here
General Math Homework
Do Practice worksheet for tomorrow.
Word Problems…A car traveled 60 miles on a road in 2 hours. How many feet per second was the car traveling? Hint: Set up the words first.
mi
hr
ft
mi
hr
s
How many seconds in an hour?
60 s 60 min 3600 s
1 min 1hr 1 hr
1 hr
3600 s
60 mi
2 hr
5,280 ft
1 mi
60 5,280
2 3600
44 ft
1 s
The car traveled 44 feet per second.
Homework
Complete Practice Worksheet B