Question 1057356
The rate at which the merchant bought 
chairs was {{{ 24/12 }}} dollars/chairs
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How much did he pay for {{{ 3 }}} chairs?
{{{ (( 24/4)) / (( 12/4 )) = 6/3 }}} dollars/chairs
So, he sold at a rate of {{{ 6/2 }}} dollars/chairs
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His rate for {{{ 12 }}} chairs is:
{{{ ( 6*6 ) / ( 6*2 ) = 36/12 }}} dollars/chairs
He charged $36 for 12 chairs
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