having a class that needs a lot of support in reading. writing, and arithmetic

1. Room 83
Introduction to
RATIOS!
Fall 2011

2. What are ratios?
• Ratios are ways that we can
compare numbers.
• In this lesson, there are three
ways you will be asked to
compare.

3. 1. part-to-part ratio
This is a ratio that compares a part
of the whole to another part of the
whole.
Example:
There are ten boys to thirteen
girls in this class.
So the ratio is written like
this:
10:13

4. Now we practice...
For the snack pile in front of you
write the ratios comparing:
a) Cheerios to squares
b) squares to raisins
c) raisins to cheerios

5. 2. part to whole ratio
This is a ratio that compares part
of the whole to the whole.
Example:
There are ten boys in a class
with twenty-three students.
So the ratio is written like
this:
10:23

6. Now we practice...
For the snack pile in front of you
write the part to whole ratios
comparing:
a) Cherrios
b) Squares
c) Raisins

7. 3. three-term ratio
This is a comparison of three
quantities with the same unit.
Example:
There are ten boys , thirteen
girls, and two teachers in our
class.
So the ratio is written like
this:

8. Now we practice...
For the snack pile in front of you
write the three term ratio
comparing all three parts of the
snack.
Cherrios to squares to raisins

9. Question #1
Write the part to
part ratios
comparing:
a) Tennis balls to
soccerballs
b) Tennis balls to
golf balls
c) Golf balls to
soccerballs

10. Question #2
Write the part to
whole ratios
comparing:
a) Tennis balls
b) Soccer balls
c) Golf balls

11. Question #3
Write the three-
term ratio
comparing the
balls in the
diagram:
Soccerballs to
tennis balls to
golf balls

12. Question #4
(a) Using your own first name, what
is the ratio comparing vowels to
consonants?
(b) Using your last name, what is
the ratio comparing vowels to
consonants?

13. In your textbook pages
266-268
Complete the following questions:
1,
6,
7,
8 (a),
9,
11,
13 (a) (b) (c),
14 (a),
17 (a)