SOLUTION: Mary purchased a prepaid phone card for $20.
Long distance calls cost 18 cents a minute using this card.
Mary used her card only once to make a long distance call.
If the rem
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-> SOLUTION: Mary purchased a prepaid phone card for $20.
Long distance calls cost 18 cents a minute using this card.
Mary used her card only once to make a long distance call.
If the rem
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Question 1089906: Mary purchased a prepaid phone card for $20.
Long distance calls cost 18 cents a minute using this card.
Mary used her card only once to make a long distance call.
If the remaining credit on her card is $11.18,
how many minutes did her call last? Answer by EMStelley(208) (Show Source):
You can put this solution on YOUR website! The original amount of the card is $20, and the final amount is $11.18.
So the difference between those two is 20.00 - 11.18 = 8.82.
This means that Mary used $8.82 worth of her phone card when she made the long distance call. If we know that each minute costs $0.18, how can we figure out how many minutes it takes to use up $8.82 worth of the phone card?
We divide. $8.82 / $0.18 = 49.
So Mary's long distance phone call had to have lasted 49 minutes. To check your answer, simply multiply 49 minutes by $0.18 to get the total cost.
