Question 1201904
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Light roast coffee beans cost seven dollars/pound, while dark roast cost $5.50 per pound. How much of each type of 
coffee is needed to create 4.50 pounds of a mixture that cost $6.75 per pound?
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Light roast coffee beans cost H dollars/pound, while dark roast cost $L per pound. How much of each type of 
coffee is needed to create M pounds of a mixture that cost $T per pound?
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If amount of the higher priced material is v, then the amount of the lower priced material is M-v.


{{{highlight_green(Hv+L(M-v)=TM)}}}


{{{Hv-Lv+LM=TM}}}

{{{(H-L)v=TM-LM}}}

{{{v=(TM-LM)/(H-L)}}}

{{{highlight_green(v=M((T-L)/(H-L)))}}}
Substitute your values to find the numeric values you want.