Achemist is mixing a 40% salt solution with a 20% salt solution to make 50 l of
a new solution that will contain 25% salt. how much of each of the original
solutions should the chemist use?

Let be the amount (in L) of the 40% solution to be used, and the amount (L) of the 20% solution. The chemist wants a new solution of 50 L, so that

Each L of the 40% solution contributes 0.4 L of salt, while each L of the 20% solution contributes 0.2. The new solution should have a concentration of 25% salt, so that

Now

maximum area = xy = (16)(32) = 512 ft2

to maximize the area of the garden, the side of the fence parallel to the side of the house should be 32 ft long, and the other two sides should both have length 16 ft.'

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