Lesson 4: Practice Problems

Problem 1

Decide whether each table could represent a proportional relationship. If the relationship could be proportional, what would the constant of proportionality be?

How loud a sound is depending on how far away you are.
distance to
listener (ft)
sound
level (dB)
$5$
$85$
$10$
$79$
$20$
$73$
$40$
$67$
The cost of fountain drinks at Hot Dog Hut.
volume
(fluid ounces)
cost
($)
$16$
$$ 1.49$
$20$
$$ 1.59$
$30$
$$ 1.89$

distance to listener (ft)	sound level (dB)
$5$	$85$
$10$	$79$
$20$	$73$
$40$	$67$

volume (fluid ounces)	cost ($)
$16$	$$ 1.49$
$20$	$$ 1.59$
$30$	$$ 1.89$

Problem 2

A taxi service charges $1.00 for the first $\frac{1}{10}$ mile then $0.10 for each additional $\frac{1}{10}$ mile after that.

Fill in the table with the missing information then determine if this relationship between distance traveled and price of the trip is a proportional relationship.

distance traveled (mi)	price (dollars)
$\frac{9}{10}$
$2$
$3 \frac{1}{10}$
$10$

Problem 3

A rabbit and turtle are in a race. Is the relationship between distance traveled and time proportional for either one? If so, write an equation that represents the relationship.

Turtle’s run:

distance (meters)	time (minutes)
$108$	$2$
$405$	$7.5$
$540$	$10$
$1, 768.5$	$32.75$

Rabbit’s run:

distance (meters)	time (minutes)
$800$	$1$
$900$	$5$
$1, 107.5$	$20$
$1, 524$	$32.5$

Problem 4

For each table, answer: What is the constant of proportionality?

$a$
$b$
$2$
$14$
$5$
$35$
$9$
$63$
$\frac{1}{3}$
$\frac{7}{3}$
$a$
$b$
$3$
$360$
$5$
$600$
$8$
$960$
$12$
$1440$
$a$
$b$
$75$
$3$
$200$
$8$
$1525$
$61$
$10$
$0.4$
$a$
$b$
$4$
$10$
$6$
$15$
$22$
$55$
$3$
$7 \frac{1}{2}$

$a$	$b$
$2$	$14$
$5$	$35$
$9$	$63$
$\frac{1}{3}$	$\frac{7}{3}$

$a$	$b$
$3$	$360$
$5$	$600$
$8$	$960$
$12$	$1440$

$a$	$b$
$75$	$3$
$200$	$8$
$1525$	$61$
$10$	$0.4$

$a$	$b$
$4$	$10$
$6$	$15$
$22$	$55$
$3$	$7 \frac{1}{2}$

Problem 5 From Unit 2 Lesson 9

Here is a table that shows the ratio of flour to water in an art paste. Complete the table with values in equivalent ratios.

cups of flour	cups of water
$1$	$\frac{1}{2}$
$4$
	$3$
$\frac{1}{2}$