Post on 21-May-2015
description
How fast will Joyanna and Ian have to drive from
Anchorage, Alaska to San Diego, California if they
plan on making it in 2 days and 15 hours?
Warm Up
Warm Up Hints
• Convert the Days into Hours.
• Use the Formula: D = RT
• D = Distance
• R = Rate (what you’re looking for)
• T = Time (Days Hours)
• Rate should be in miles per hour (mph)
3,759 miles divided by 48.25
hours = 77.9 or 80 miles per hour.
Warm Up
Review of Customary Units, Fractions, and Dimensional
Analysis.
By Ms. Dewey-Hoffman
November 12th, 2008
Chapter 5, Section 5
(if you must know)
Example of Conversion Factors
To find a COMMON DENOMINATOR
between Two Fractions,
you MULTIPLY one or both
fractions by a Conversion Factor.
A Conversion Factor is always equal to 1.
H – 4 = 7 5 9
Example of Conversion Factors
1) Add 4/5 to both sides to cancel out –4/5 and get H by itself.
H – 4 + 4 = 7 + 4 5 5 9 5
2) Multiply both 7/9 and 4/5 by a conversion factor.
H = 7 (5) + 4 (9) 9 (5) 5 (9)
3) 5/5 and 9/9 are Conversion Factors.
This is the Same with Conversion Factors in Converting Units!
Use Equivalent Units To Write A Conversion Factor.
Like: 12 inches = 1 foot.They Are Equivalent!
Also: 4 quarts = 1 gallon.They Are Equivalent!
Also: 24 hours = 1 day.They Are Equivalent!
Turn The Conversions Into Fractions…They’re Equivalent
• Just Write These Equivalents to Make a Fraction that is Equal to 1.
12 inches = 11 foot
2 cups = 18 Fluid Ounces
Dimensional AnalysisThe process of analyzing units to decide
which conversion factors to use.When you are looking at the Legend on your
handout, that’s Dimensional Analysis!
This is a Fraction Bar
These Bars mean
Multipl-ication and
separate fractions or Conversion
Factors.
10 quarts = ? gallons
10 Quarts ? Gallons
Conversion Factor Goes Here
4 Quarts
1 Gallon
Now turn it into a Fraction/Multiplication Problem
10 ¼ = 2 ½ gallons
10 quarts = 2 ½ gallons
This is a Fraction Bar
These Bars mean
Multipl-ication and
separate fractions or Conversion
Factors.
Dealing with Mixed Numbers and Conversions?
3 3/16 yards = ? inches
1) Change Mixed Number to an Improper Fraction, then Convert.
51 Yards
1 Yard
3 Feet
1 Foot
12 Inches
16
2) Take the answer and Change to a Mixed Number.
Notice how the IMPROPER Fraction looks like a Fraction
on the T graph.
(51 3 12) (16 1 1) = 114.75 or 114 ¾
To Compare Different Units…
Change ONE Unit into the other and see which is bigger, less, or equal.
Inequalities Anyone?
10 Gallons ____ 42 Quarts
1) 42 Quarts is how many gallons?
2) 4 Quarts for every 1 Gallon. (42/4 = 10 ½ Gallons)
3) Which is bigger? 42 Quarts or 10 Gallons?
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Assignment #36
Finish The Handout From Friday.
Work Should be Shown on Another Sheet of Paper, WHERE THE PROBLEMS ARE NUMBERED, and Stapled to the Back of
the Handout.