How much credit is left on the prepaid phone card?
Question:
If 75 units of credit have been used on a prepaid phone card with an initial credit of $20.75 and a decrement of $0.09 per unit of use, how much credit is left on the card?
Answer:
The remaining credit on the prepaid phone card can be calculated using the equation C(x)=20.75-0.09x.
To calculate the remaining credit on the prepaid phone card after using 75 units of credit, we substitute x=75 into the equation:
C(75) = 20.75 - 0.09(75)
C(75) = 20.75 - 6.75
C(75) = 14
Therefore, there is $14 credit left on the prepaid phone card after using 75 units.