document.write( "Question 253013: If a, b, and c are positive numbers such that 3a = 4b = 5c, and if a + b = kc, what is the value of k ?\r
\n" ); document.write( "\n" ); document.write( "(A) 12/35 (B) 5/7 (C) 10/7 (D) 7/5 (E) 35/12 \n" ); document.write( "

Algebra.Com's Answer #185247 by JimboP1977(311) $\"\"$ $\"About$

You can put this solution on YOUR website!
$\"%28a%2Bb%29%2Fc=k\"$
\n" ); document.write( "Express left handside in terms of a.
\n" ); document.write( " $\"%28a%2B%283%2F4%29a%29%2F%28%283%2F5%29a%29=k\"$
\n" ); document.write( " $\"%28%287%2F4%29a%29%2F%28%283%2F5%29a%29=k\"$
\n" ); document.write( " $\"%28%287a%2F4%29%2A%285%2F3a%29%29=k\"$
\n" ); document.write( " $\"35a%2F12a=k\"$
\n" ); document.write( "The a terms cancel to give
\n" ); document.write( " $\"35%2F12=k\"$ \n" ); document.write( "

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