Transcript ratio - Miami Beach Senior High School

EOC Practice
24.
25.
x + (2x + 0.15) + (x + 0.05) = 1.8
Which of the following is the value of x?
a) 0.40
b) 0.45
c) 0.53
d) 0.96
50(t – 1) = 30t
What is the value of t?
26.
Just in case:
The equation at the top is b = 24 – 2s
Solve for s
27.
Name:
Period:
Date:
Topic: Ratios, Rates, and Conversions
Essential Question: How can I write ratios & unit rates to
compare quantities?
Vocabulary:
1. Ratios
2. Rates
3. Conversion
A ratio is the comparison of two numbers written as a fraction.
For example: Your school’s basketball team has won 7 games
and lost 3 games. What is the ratio of wins to
losses?
Because we are comparing wins to losses the first
number in our ratio should be the number of wins and
the second number is the number of losses.
The ratio is
games
won
_________
=
games lost
7_______
games
=
3 games
7
__
3
RATIOS
A ratio makes a comparison. There
are 3 green aliens and 4 purple
aliens. The ratio of
green aliens to
purple aliens is
3 to 4.
RATIOS
A ratio makes a comparison. The
ratio of green aliens to total aliens
is 3 to 7. What is the
ratio of total aliens to
purple aliens?
The ratio of total
aliens to purple
aliens is 7 to 4.
RATIOS
A ratio makes a comparison. Ratios
can be written in three different
ways.
3 to 4
3:4
3
4
Could we apply this concept?
1) You are shopping for T-shirts. Which store
offers the best deals?
Store A: $25 for 2 shirts
Store B: $45 for 4 shirts
Store C: $30 for 3 shirts
2) Which is the better buy?
Deal #1: $3.29 for 6 Bagels
Deal #2: $4.15 for 8 Bagels
In a ratio, if the numerator and denominator are measured in
different units then the ratio is called a rate.
A unit rate is a rate per one given unit, like 60 miles per 1 hour.
Example: You can travel 120 miles on 60 gallons of gas.
What is your fuel efficiency in miles per gallon?
________
miles = ________
2 miles
Rate = 120
60 gallons 1 gallon
Your fuel efficiency is 2 miles per gallon.
RATES
A rate is a ratio that compares quantities that
are measured in different units.
This spaceship travels at a certain speed.
Speed is an example of a rate.
Speed can be measured in many different ways.
This spaceship can travel
100 miles in 5 seconds. 100 miles in 5 seconds is a rate.
RATES
A rate is a ratio that compares quantities that
are measured in different units.
Rates are often written in fraction form.
100 miles in 5 seconds is a rate.
It can be written as…..
100 Miles
5
Seconds
RATES
A rate is a ratio that compares quantities that
are measured in different units.
One key word that often identifies a rate is PER.
Miles per gallon, Points per free throw,
Dollars per pizza, Sticks of gum per pack
Conversions
• Conversion factor – a ratio of two
equivalent measures in different units that
always equals one
Conversions:
How do you convert 330 minutes to hours?!?
Hint:
Big to Small
 Multiply
15kg to grams --- convert to grams
Small to Big
 Divide
5feet and 3 inches --- convert to inches
Conversions:
•
Hint:
Big to Small
 Multiply
How many centimeters are in 1 kilometers?
120 min; s
8 hr; min
120 meters; cm
5 mi; ft
Small to Big
 Divide
How many inches are in 5yd 4ft?
Independent Practice:
35 km; cm
Hint:
Big to Small
 Multiply
Small to Big
 Divide
23 days; hours
80ft; yd
Car 1 drove 476 miles in 7 hours and
Car 2 drove 438 miles in 6 hours during
the cross-country road race. Who had
the fastest average speed?
Reference Sheet:
Conversions
1 cup = 8 fluid ounces
1 yard = 3 feet = 36 inches
1 pint = 2 cups
1 mile = 1,760 yards = 5,280 feet
1 quart = 2 pints
1 acre = 43,560 square feet
1 gallon = 4 quarts
1 hour = 60 minutes
1 pound = 16 ounces
1 minute = 60 seconds
1 ton = 2,000 pounds
1 liter = 1000 milliliters = 1000 cubic centimeters
1 meter = 100 centimeters = 1000 millimeters
1 kilometer = 1000 meters
1 gram = 1000 milligrams
1 kilogram = 1000 grams
Hint:
Big to Small --- Multiply
Small to Big --- Divide
Wrap-up:
• Reminder:
Vocabulary Review, Summary, and
Left column questions