If the cost of a telephone conversation varies directly as the length of the time of conversation, and if the cost of six minutes is $0.90, what would be the cost for a nine-minute call?
2 Answers
Aug 5, 2018
Cost for a
Explanation:
Let length of time be
equation is
Cost for a
Aug 5, 2018
Cost =
Explanation:
As the cost is proportional to the time you can set up a direct proportion using equivalent fractions: