Question 1146648
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... needs 80 liters of a 50% alcohol solution. she has available of a 20% and 80% alchol solution. how many liters of each solution should she mix to obtain 80 liters of a 50% alcohol soultion?
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v, liters volume of the 80%
M=80
M-v, liters volume of the 20%
T=50
H=80
L=20


{{{Hv+L(M-v)=TM}}}--------solve for v.


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

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

{{{(H-L)v=M(T-L)}}}

{{{highlight(v=M((T-L)/(H-L)))}}}
Substitute given values and evaluate v and M-v.