SOLUTION: Dr. Jekyll needs 12 liters of a 40% solution to become Mr. Hyde. He must mix a 20% solution and a 50% solution. How many liters of each will be required to obtain what he needs?

Question 1104555: Dr. Jekyll needs 12 liters of a 40% solution to become Mr. Hyde.
He must mix a 20% solution and a 50% solution. How many liters of
each will be required to obtain what he needs?
Answer by josmiceli(19441) (Show Source): You can put this solution on YOUR website!
Let = liters of 20% solution needed
Let = liters of 50% solution needed
-----------------------------------------
(1)
(2)
-----------------------------------
(2)
(2)
Multiply both sides of (1) by
and subtract (1) from (2)
------------------------------------
(2)
(1)
------------------------

and
(1)
(1)
-----------------------------------
4 liters of 20% solution are needed
8 liters of 50% solution are needed
------------------------------------
check:
(2)
(2)
(2)
(2)
(2)
OK

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