Question 163951
let C = cost to rent
let D = number of days
let M = number of miles.
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formula is:
C = ($65.00 * D) + ($.3 * M)
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in your problem,
C = $275.00
D = 3
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substitute known values in equation.
$275.00 = $65.00 * 3 + $.3 * M
perform indicated operations.
$275.00 = $195.00 + $.3 * M
subtract 195 from both sides of equation.
$275.00 - $195.00 = $.3 * M
perform indicated operations.
$80.00 = $.3 * M
divide both sides of equation by $.3
$80.00 / $.3 = M
perform indicated operations.
266.6666666667 = M
which is the same as
266 + 2/3 = M (.666666667 is same as 2/3)
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answer is 266 and 2/3 miles.
not sure how you got 400 but it isn't right.
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plugging values into original equation will help you to see this.
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C = 3*65 + .3*(400) = 195 + 120 = 315 (not equal to 275)
C = 3*65 + .3 (266 + 2/3) = 195 + 79.8 + .2 = 195 + 80 = 275
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