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Aldo purchased a prepaid phone card for $45.75. Calls cost 7 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)=45.75-0.07x
How much credit is left on the card after Aldo uses it for 20 minutes of calls?

User Roman C
by
3.8k points

2 Answers

5 votes

Answer: 44.35

Explanation:

0.07x20=1.4

45.75-1.4

User Wicaledon
by
3.3k points
4 votes
Answer is $44.35 credit left on the card

Step by step

C(x) = 45.75 - .07x

x = 20 minutes

C(x) = 45.75 - (.07) (20)

C(x) = 45.75 - 1.40 = $44.35 left on the card
User Kahsius
by
3.4k points