Linear Equations and Inequalities Word Problems

David is running a concession stand at a soccer game. He sells nachos and sodas. Nachos cost $1.50 each and sodas cost $0.50 each. At the end of the game, David made a total of $78.50 and sold a total of 87 nachos and sodas combined. Which system of equations represents this situation?

• 1.5x+0.5y=78.5
  x+y=87

• 1.5x+0.5y=78.5
  1.5x+0.5y=87

• x+y=78.5
  1.5x+0.5y=87

• x+y=78.5
  x+y=87

A willow tree is 5.1 feet tall and grows at a rate of 2.5 feet a year. After how many years will the tree have reached no more than 60 feet tall?

• 5.1 + 2.5y ≥ 60

• 60 < 5.1 + 2.5

• 5.1 + 2.5y ≤ 60

• 5.1 + 2.5y > 60

Write the system of inequalities
Carlos works at a movie theater selling tickets. The theater has 300 seats and charges $7.50 for adults and $5.50 for children. The theater expects to make at least $2000 for each showing

• x+y≤300
  7.5x+5.5y≥2000

• x+y<300
  7.5x+5.5y≥2000

• x+y≤300
  7.5x+5.5y≤2000

• x+y>2000
  7.5x+5.5y≤300

JoAnn likes her job as a baby-sitter, but it pays only $3 per hour. She has been offered a job as a tutor that pays $6 per hour. Because of school, her parents only allow her to work a maximum of 15 hours per week. How many hours can JoAnn tutor and baby-sit and still make at least $66 per week? How much does she make?

• b + t < 15
  3b + 6t > 66

• b + t > 15
  3b + 6t < 66

• 3b + 6t > 15
  b + t < 66

• 3b + 6t < 15
  b + t < 66

Sam make $10.25 per hour working at Cheddars.  He plans to buy a laptop for $550.  Write and solve an inequality describing how many hours h Sam will have to work to be able to buy the laptop. (Round to the next higher hour)

• 10.25h < 550; less than 54 hours

• 10.25h > 550; greater than 54 hours

• 10.25h ≤ 550; at most 54 hours

• 10.25h ≥ 550; at least 54 hours

Erin can read at least 80 words per minute. Write an inequality to show this situation. 

• x > 80

• x < 80

• x ≥ 80

• x ≤ 80

Four times a number increased by  7 is at least 19. 

• 4x > 19

• 4x + 7 ≥ 19

• 4x < 19

• 4x + 7 ≤ 19

Mona is ordering cups for her school.  Company A charges $3.50 for each cup and a one-time starter fee of $14.  Company B charges $0.50 for each trophy and a one-time starter fee of $22.  
Which inequality can be used to find x, the minimum number of cups that can be ordereed so that the total charge at Company A is less than the total charge at Company B?

• 3.5x + 14 < 0.5x + 22

• 3.5x + 14 > 0.5x + 22

• 3.5 + 14x < 0.5 + 22x

• 3.5 + 14x > 0.5 + 22x

Ross and Chandler go to Taco Land and order sodas for a total of $3.50. They also want to order some tacos (of course), which cost $1.75 each. If they have $20, how many tacos can they buy? Which inequality best represents the situation.

• 3.50 + 1.75t > 20

• 1.75 + 3.50t ≤ 20

• 3.50 + 1.75t ≥ 20

• 1.75t + 3.50 ≤ 20

Luka and Dana are making cookies for the Westland Pantry. They only have up to 6 hours to bake! They can bake 32 chocolate chip cookies in an hour (x), and 20 snickerdoodle cookies in an hour (y). They need to make at least 150 cookies. Which one of these is a valid solution?

• (3, 2)

• (1, 4)

• (2, 8)

• (5, 1)