Question 1158234
v of the 15%
50-v of the 10%


{{{15v+10(50-v)=12*50}}}
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{{{15v-10v+10*50=12*50}}}
{{{v(15-10)=12*50-10*50}}}
{{{highlight_green(v=50((12-10)/(15-10)))}}}

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