Question 1062399
You want to learn to solve any general coffee mix problem as if like :
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To make a mixture of M pounds of coffee worth $T a grocer mixes coffee worth $L a pound with coffee worth $H a pound .How many pounds of the cheaper coffee should the grocer use?  (Assumes that {{{L<H}}}).
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Account for the amount of mixture:  
Let u be quantity of the lower priced coffee
Let v be quantity of the higher priced coffee
{{{u+v=M}}}


Account for the cost of the mixture:
{{{uL+vH=T}}}


Linear System of Equations in Unknowns v and u:
{{{system(u+v=M,and,uL+vH=T)}}}


Solve the system for u and v.