Bunuel wrote:
United Telephone charges a base rate of $10.00 for service, plus an additional charge of $0.25 per minute. Atlantic Call charges a base rate of $12.00 for service, plus an additional charge of $0.20 per minute. For what number of minutes would the bills for each telephone company be the same?
A. 2 minutes
B. 10 minutes
C. 20 minutes
D. 40 minutes
E. 60 minutes
Kudos for a correct solution.
Let x = the number of minutes used
United Telephone charge =
$10.00 + $0.25xAtlantic Call charge =
$12.00 + $0.20xFor what number of minutes would the bills for each telephone company be the same? In other words, for what value of x does
$10.00 + $0.25x EQUAL
$12.00 + $0.20x?
Let's find out....
10.00 + 0.25x =
12.00 + 0.20xSubtract 10 from both sides to get: 0.25x = 2 + 0.20x
Subtract 0.20x from both sides to get: 0.05x = 2
Solve: x = 2/0.05 = 40
ASIDE: If you're not crazy about dividing by decimals, you can always take 2/0.05 and create an EQUIVALENT fraction first.
Take: 2/0.05
Multiply top and bottom by 100 to get: 200/5, which equals 40
Answer: D
Cheers,
Brent
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