Review Unit 2 – Whole Number
Ratios and Proportions
Common Core Standards
7.RP.2. Recognize and represent proportional relationships between
quantities.
a.  Decide whether two quantities are in a proportional relationship, e.g., by
testing for equivalent ratios in a table or graphing on a coordinate plane
and observing whether the graph is a straight line through the origin.
b. Identify the constant of proportionality (unit rate) in tables, graphs,
equations, diagrams, and verbal descriptions of proportional
relationships.
c. Represent proportional relationships by equations. For example, if total
cost t is proportional to the number n of items purchased at a constant
price p, the relationship between the total cost and the number of items
can be expressed as t = pn.
d. Explain what a point (x, y) on the graph of a proportional relationship
means in terms of the situation, with special attention to the points (0, 0)
and (1, r) where r is the unit rate.
WARM-UP (1)
Write and solve the proportion.
1) The ratio of boys to girls in the class was 5 to 6. If
there were 30 boys, how many students were girls?
2) A 4 inch by 6 inch photo needed to be enlarged so that
the long side would be 24 inches. What is the length
of the enlarged short side?
Whole Number Ratios and
Proportions
We can represent proportions as equivalent fractions,
in a table, with an equation, or on a graph.
h (hrs)
M = 50h (miles)
0
0
1
50
2
100
3
150
4
200
Miles (M)
50 100 150 200
=
=
=
1
2
3
4
200
150
100
50
0
0
2
4 6
H (hours)
8
10
REVIEW (2)
The triangles are proportional. Find the length of the
missing side.
?
10
12
30
Steve made 16 out of 24 basketball free throws. How
many would we expect him to make if he shot 36 free
throws?
REVIEW (3)
Is the relationship proportional? If so, find the
constant of proportionality (k).
Sam drove 240 miles in 4 hrs. Cindy drove 360 miles
in 6 hours.
At one amusement park it's $6 for 20 rides. At another
it's $4 for 15 rides.
REVIEW (4)
Is the ratio of cashews to peanuts as shown in the
table a proportional relationship? If so, find the
constant of proportionality, and write an equation.
Peanuts
Cashews
3
2
6
4
9
6
12
8
Is the ratio of miles traveled to hours driving shown in
the table a proportional relationship? If so, find the
constant of proportionality, and write an equation.
Hours
Miles
1 2 3 4
20 30 40 50
REVIEW (5)
Fill in the table to complete the proportional relationship.
Find the constant of proportionality.
Gallons
Miles
1
24
2
4
72
REVIEW (6)
Plot the data and draw a ray through the points. Is the
relationship proportional? If so, find "k," and write an
equation.
Cost (C)
Rent a Boat
Hours (h) Cost (c)
96
1
36
72
2
72
3
108
4
144
48
24
0
0
2
4
6
Hours (h)
8
10
REVIEW (7)
Fill in the table using the data about miles per gallon. If
the relationship is proportional, find the constant of
proportionality, fill in the table, and write an equation.
Miles (M)
Gallon
40
1
30
30
3
20
4
10
0
0
Miles
2
4
6
Gallons (g)
8
10
REVIEW (8)
Fill in the table using the data about the cost of
carrots from the graph. If the relationship is
proportional, find the constant of proportionality, and
write an equation.
Apples (a) 1
3
4
Cost (C)
6
Cost (C)
48
36
24
12
0
0
2
4 6
8
Apples (a)
10
REVIEW (9)
One employee received pay at a constant rate that can
be represented by a proportional equation. Identify the
employee and write the equation in terms of Pay (P)
and hours (h)?
Pay ($)
Hours
Al
Bob
Cal
2
40
50
20
4
50
100
50
6
60
150
80
8
70
200
110
Correct Employee__________
Equation __________
PRACTICE (10)
If Team B continues at the same pace, how many games
would we expect them to win if the played 45 games?
Wins
Losses
Games
Played
Team A
7
5
12
Team B
5
4
9
Team C
2
8
10
PRACTICE (11)
Sally has a 4 inch by 6 inch photo she wants to
enlarge. She has two choices "12 by 20" or "24 by 36."
Decide which size to choose so that she won't have to
alter the proportions of her original picture.
4in
6in
FINAL QUESTION (12)
Does each ray represent a proportional relationship?
y
8
6
4
2
0
0
2
4
6
8
10
x