Question 1108035
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Donna wants to make trail mix made up of almonds, walnuts, and raisins. She wants to mix one part almonds, 
two parts walnuts, and three parts raisins. Almonds cost $12 per pound, walnuts cost $9 per pound, 
and raisins cost $5 per pound.
Donna has $15 to spend on the trail mix. Determine how many pounds of trail mix she can make. (have an algebraic solution)
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Let's combine 1 pound of almonds, 2 pounds of walnuts, and 3 pounds of raisins.

This combination is the prescribed proportion. The total mass of this mixture is 1 + 2 + 3 = 6 pounds,

and its total cost is  1*$12 + 2*$9 + 3*$5 = $45.



So, 6 pounds of this mixture cost 45 dollars.



$15 dollars that Donna has  is  1/3  of  $45 - - - hence, 
for  $15  Donna may have  1/3  of  6  pounds,  i.e.  2 pounds of the mixture.


<U>ANSWER</U>.  For $15, Donna may have 2 pounds of the mix.
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