Real World Problem Equations

What equation matches this situation?
Robyn had some video games then bought 4 more.  Now she has a total of 10 games.

• v - 4 = 10

• v + 4 = 10

• 10 - 4 = v

• Answer not Given

Which equation correctly represents this scenario: Apples cost $2 per pound, a. How many pounds of apples can you buy for $20?

Cheryl gets paid $8 per hour, h, for her job at the record store. She made a total of $96 last week. Which equation models this situation?

• 96h = 8

• h/96 = 8

• 8h = 96

• h/8 = 96

Which choice models this situation? Lisa finished a race in 58 seconds. This was 4 seconds less than her best practice time, t. What was Lindsey's best practice time?

• t + 4 = 58

• t - 4 = 58

• 4t = 58

• t/4 = 58

Shayla has $200 and makes $17 per hour. Which equation represents the total amount of money Shayla has after working x hours?

• y = 17x + 200

• y = 17 + 200x

• y = 200 + 17

The cost, c, to park in a parking garage can be represented using the equation c = 5 + 0.5h, where h is the number of hours the car is in the parking garage. Which of these statements is TRUE?

• It costs $0.50 to park in the garage for 1 hour.

• It costs $5 to park in the garage for 1 hour.

• It costs $5 per hour to park in the garage.

• It costs $6 to park in the garage for 2 hours.

Mathematical Equivalence

ON

Answer explanation

y = x + 8 | This tree is 8 feet tall and growing 1 foot each year.

y = x/2 + 10 | This tree is 10 feet tall and growing 1/2 foot each year.

Substitute x + 8 for y in 2nd equation

x + 8 = x/2 + 10

x - x/2 + 8 -8 = x/2 - x/2 + 10 -8

x/2 = 2 | x = 4 years

Joe’s Canoes charges an initial fee of $20 plus $4 an hour. Callie’s Canoes charges a flat rate of $14 an hour. Find the number of hours for which the total amount that both places charge would be the same.

• 3 hours

• 4 hours

• 1 hour

• 2 hours

The Roaming Cell Phone Company charges $15.00 per month plus $0.20 per minute of airtime usage. If Juanita uses x minutes of airtime, what is an equation that can be used to determine her monthly cell phone bill? The equation is y=0.20x+15. What does the y mean?

• amount of minutes

• total cost

• cost per minute

• variable

• flat fee

Jimbo has $100 in his bank account. Every week he deposits $30 more dollars. Write an equation to represent the amount of money he has in his bank account 

• y = 100 - 30x

• y = 100 + 30x

• y = 100x + 30

• y = 100x - 30