Lesson 8: Practice Problems

Problem 1

A car dealership pays $8,350 for a car. They mark up the price by 17.4% to get the retail price. What is the retail price of the car at this dealership?

Problem 2

A store has a 20% off sale on pants. With this discount, the price of one pair of pants before tax is $15.20. What was the original price of the pants?

$3.04
$12.16
$18.24
$19.00

Problem 3

A music store marks up the instruments it sells by 30%.

If the store bought a guitar for $45, what will be its store price?
If the price tag on a trumpet says $104, how much did the store pay for it?
If the store paid $75 for a clarinet and sold it for $100, did the store mark up the price by 30%?

Problem 4

A family eats at a restaurant. The bill is $42. The family leaves a tip and spends $49.77.

How much was the tip in dollars?
How much was the tip as a percentage of the bill?

Problem 5

The price of gold is often reported per ounce. At the end of 2005, this price was $513. At the end of 2015, it was $1060. By what percentage did the price per ounce of gold increase?

Problem 6 From Unit 5 Lesson 4

A phone keeps track of the number of steps taken and the distance traveled. Based on the information in the table, is there a proportional relationship between the two quantities? Explain your reasoning.

number of steps	distance in kilometers
$950$	$1$
$2, 852$	$3$
$4, 845$	$5.1$

Problem 7 From Unit 6 Lesson 6

A college student takes out a $7,500 loan from a bank. What will the balance of the loan be after one year (assuming the student has not made any payments yet):

if the bank charges 3.8% interest each year?
if the bank charges 5.3% interest each year?

Problem 8 From Unit 6 Lesson 2

Match the situations with the equations.

Mai slept for $x$ hours, and Kiran slept for $\frac{1}{10}$ less than that.
Kiran practiced the piano for $x$ hours, and Mai practiced for $\frac{2}{5}$ less than that.
Mai drank $x$ oz of juice and Kiran drank $\frac{4}{3}$ more than that.
Kiran spent $x$ dollars and Mai spent $\frac{1}{4}$ less than that.
Mai ate $x$ grams of almonds and Kiran ate 1.5 times more than that.
Kiran collected $x$ pounds of recycling and Mai collected $\frac{3}{10}$ less than that.
Mai walked $x$ kilometers and Kiran walked $\frac{3}{8}$ more than that.
Kiran completed $x$ puzzles and Mai completed $\frac{3}{5}$ more than that.

$y = 2.33 x$
$y = 1.375 x$
$y = 0.6 x$
$y = 0.9 x$
$y = 0.75 x$
$y = 1.6 x$
$y = 0.7 x$
$y = 2.5 x$