Problem #878

878.

Chandra pays an on-line service provider a fixed monthly fee plus an hourly charge for connect time. Her December bill was $$12.48$, but in January her bill was $$17.54$ because she used twice as much connect time as in December. What is the fixed monthly fee?

$\mathrm{(A)} $2.53 \qquad\mathrm{(B)} $5.06 \qquad\mathrm{(C)} $6.24 \qquad\mathrm{(D)} $7.42 \qquad\mathrm{(E)} $8.77$

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Instructions for entering answers:

  • Reduce fractions to lowest terms and enter in the form 7/9.
  • Numbers involving pi should be written as 7pi or 7pi/3 as appropriate.
  • Square roots should be written as sqrt(3), 5sqrt(5), sqrt(3)/2, or 7sqrt(2)/3 as appropriate.
  • Exponents should be entered in the form 10^10.
  • If the problem is multiple choice, enter the appropriate (capital) letter.
  • Enter points with parentheses, like so: (4,5)
  • Complex numbers should be entered in rectangular form unless otherwise specified, like so: 3+4i. If there is no real component, enter only the imaginary component (i.e. 2i, NOT 0+2i).

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