Dr. Don offers a tutoring service for college students. He charges $40 as a fixed rate for the first hour plus $20 for each additional hour. What is the minimum and maximum number of hours of tutoring a student can get if he or she can afford to spend between $140 and $200? (Express your answer as an inequality)

Answer: 6 ≤ h ≤ 9

Step-by-step explanation:

Hi, since He charges $40 as a fixed rate for the first hour plus $20 for each additional hour, the cost of the tutoring service is equal to the fixed rate (40) plus, the product of the additional hours (h-1) and the cost per additional hour (20).

40+20 (h-1)

40+20h-20

20+20h

Since a student can spend between $140 and $200, the previous expression must be greater o equal than 140, and less or equal than 200.

140≤20+20h≤200

Subtracting 20

140-20 ≤20-20+20h ≤200-20

120 ≤ 20h ≤ 180

Dividing by 20

120/20 ≤ 20h/20 ≤ 180/20

6 ≤ h ≤ 9