Word Problems
A babysitter earns $12 per hour. Write an equation showing how much money m she earns after h hours.
m=12h
Simplify:
12:18
2:3
Maria buys apples.
Is this relationship proportional? Explain why.
Yes. The unit rate is always $4 per apple, so the relationship is proportional.
A point is located at (3,7).
How many units right? How many units up?
3 right, 7 up
Find the area of a rectangle with length 9 and width 6.
54
A gym charges $25 each month. Write an equation for the total cost after m months.
c=25m
Find the missing value.
5/8 = x/24
A taxi charges:
Is this relationship proportional? Explain why.
No. The unit rate is not constant (6 ÷ 1 = 6, 11 ÷ 2 = 5.5, 16 ÷ 3 ≈ 5.3), so it is not proportional.
The point (4,12) is on a proportional graph.
What is the constant of proportionality?
3
A scale drawing has a scale factor of 3. A side measures 5 cm. What is the new length?
15cm
A baker uses 4 cups of flour for every 10 cookies. How many cups are needed for 25 cookies?
10 cups
A map uses a scale of 1 inch = 6 miles.
How many miles is 8 inches?
48 miles
The equation is
y=9x
Proportional or not?
Proportional
A graph passes through
(0,0)
(2,10)
What is the unit rate?
5
A shape is enlarged by a scale factor of 4. Its area was 12 square units. What is the new area?
A recipe uses 3 cups of juice for every 8 cups of punch. If you use 12 cups of juice, how much punch will you make?
32 cups
A paint mixture uses 2 cups blue for every 5 cups white.
If you have 10 cups of white paint, how much blue paint is needed?
4 cups
The equation is
y=7x + 2
Not proportional
Which graph represents a proportional relationship?
A. Line through (0,0)
B. Line through (0,3)
A
Pattern:
Figure 1 = 4 tiles
Figure 2 = 7 tiles
Figure 3 = 10 tiles
How many tiles are in Figure 6?
19
Create an equation for:
A company pays $18 per hour plus a one-time $40 bonus.
p=18h+40
A class has 18 boys and 12 girls.
What is the ratio of girls to total students?
12:30 = 2:5
A graph is a straight line but does NOT pass through the origin.
Is it proportional?
No
A graph contains the point
(6,18)
Predict the point when x = 10.
(10,30)
A graph contains the points
(2,8)
(4,16)
(6,24)
Write the equation and explain why the relationship is proportional.