Question 237503: Word problems have always confused me. I need help in deciphering exactly what the following word problem is looking for:
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-500) + 46.95, where it is assumed that t > 500 minutes. What times will keep costs between $87.45 and $118.95?
Any help would eb appreciated. Thank you in advance for your help.
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! 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-500) + 46.95, where it is assumed that t > 500 minutes. What times will keep costs between $87.45 and $118.95?
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87.45 < 0.25(t-500) + 46.95 < 118.95
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subtract 46.95 along the line to get:
40.50 < 0.25(t-500) < 72
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Divide thru by 0.25 to get:
162 < t-500 < 288
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Add 500 along the line to get:
662 < t < 788
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Cheers,
stan H.
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