Question 1182442
v of the long sleeved
40-v of the short sleeved

{{{12.75v+9.9(40-v)=421.65}}}

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{{{12.75v+9.9*40-9.9v=421.65}}}

{{{(12.75-9.9)v+9.9*40=421.65}}}

{{{highlight_green(v=(421.65-9.9*40)/(12.75-9.9))}}}

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