SOLUTION: A cellular phone company offers a contract for which the cost C, in dollars, of t minutes of telephoning is given by C=0.25(t-400)+43.95, where it is assumed that t is greater than

Algebra ->  Expressions-with-variables -> SOLUTION: A cellular phone company offers a contract for which the cost C, in dollars, of t minutes of telephoning is given by C=0.25(t-400)+43.95, where it is assumed that t is greater than      Log On


   



Question 263013: A cellular phone company offers a contract for which the cost C, in dollars, of t minutes of telephoning is given by C=0.25(t-400)+43.95, where it is assumed that t is greater than or equal to 400 minutes. What times will keep costs between $87.70 and $123.95?
Answer by richwmiller(17219) About Me  (Show Source):
You can put this solution on YOUR website!
plug in 87.70 for c . that will be the lower limit for t t=575
plug in 123.95 for c that will be the upper limit for t t=720
575 < t < 720