Lesson 12: Practice Problems

Problem 1

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 2

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 3

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 4 From Unit 2 Lesson 7

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 5 From Unit 4 Lesson 4

Noah picked 3 kg of cherries. Mai picked half as many cherries as Noah. How many total kg of cherries did Mai and Noah pick?

$3 + \frac{1}{2}$
$3 - \frac{1}{2}$
$(1 + \frac{1}{2}) \cdot 3$
$1 + \frac{1}{2} \cdot 3$