Problem #1435


Points $B$ and $C$ lie on $AD$. The length of $AB$ is $4$ times the length of $BD$, and the length of $AC$ is $9$ times the length of $CD$. The length of $BC$ is what fraction of the length of $AD$?

$\mathrm{(A)}\ 1/36\qquad\mathrm{(B)}\ 1/13\qquad\mathrm{(C)}\ 1/10\qquad\mathrm{(D)}\ 5/36\qquad\mathrm{(E)}\ 1/5$

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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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