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1 vote
Helpp please

Amy purchased a prepaid phone card for $15.00. Calls cost 15 cents a minute using this card. The credit, C (in dollars), left on the card after it is used for x minutes of calls is given by the following function.

C(x)=15.00-0.15x

How much credit is left on the card after Amy uses it for 30 minutes of a call?

2 Answers

4 votes

Answer:

10.5

Explanation:

C(x)=15.00-0.15xx

=15.00-0.15(30)

=15.00-4.5

=10.5

User Ramie
by
7.5k points
5 votes

Explanation:

We can use the given function:

C(x) = 15.00 - 0.15x

to find the credit left on the card after using it for 30 minutes:

C(30) = 15.00 - 0.15(30)

= 15.00 - 4.50

= 10.50

Therefore, the credit left on the card after Amy uses it for 30 minutes of a call is $10.50.

User Taoufik Mohdit
by
7.6k points