Linear Word Problems

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 (C)?

• C = 0.20x + 15
• C =15 (0.20x)
• C = 15 + x + 0.20
• C = 0.20 + 15x

Jenny went to the sale at Kohl's last weekend.  
T-shirts were on sale for $15 each and hoodies were on sale for $20 each.  If she spent $150 total, write an equation to represent this situation.  

• 20x + 15 = y 
• 35x = y 
• 15x + 20y = 150 
• 150 - 20x = 15y 

A man is climbing down from 100 feet high descending 30 feet per minute.

• y = 100 - 30x
• y = 100 + 30x
• y = 100x + 30
• y = 100x - 30

Write an linear equation to model the following:
You want to buy desserts, ice-cream is $2.50 per scoop and puppychow is $4 per bag and you want to spend $20. 

• y=2.50x+4
• 2.50x+4y=20
• y=4x+2.5

Bob has $150 in his savings account and saves $40 per month.  Which equation represents the amount Bob has in his account after x months?

• y = 150 + 40
• y = 40x + 150
• y = 150x + 40

A holiday meal costs $12.50 a person plus a delivery fee of $30.  Which equation represents the amount a holiday meal costs, including delivery, for x people?

• y = 30 + 12.5x 
• y = 12.5 + 30
• y = 12.5 + 30x

Easy Car Rental charges $8.50 an hour plus a rental fee of $25.50. Which equation represents the total charges for x hours?

• y = 8.5 + 25.5
• y = 25.5 + 8.5x
• y = 8.5 + 25.5x

Sandra has a $20 itunes gift card and spends $3 each month.  Which equation can be used to find how much money Sandra has on her giftcard after x months?

• y = 3x + 20
• y = 3 + 20x
• y = -3x + 20
• y = -20x + 3