Question

Jotham needs 70 liters of a 50% alcohol solution. He has a 30% solution and an 80% solution available. How many liters of

Answer 1

x+y=70. (30x+80y)/(100x+100y)=50/100

Answer 2

Answer:

42 liters of 30% alcohol solution will be needed.

28 liters of 80% solution will be needed.

Step-by-step explanation:

Jotham needs 70 liters of a 50% alcohol solution.

Let the 30% solution needed be x.

We get the following equation:

$70\times0.5=0.30x+0.80(70-x)$

Solving this we get;

$35=0.30x+56-0.80x$

=> $35=56-0.50x$

=> $0.50x=56-35$

=> $0.50x=21$

x = 42

Hence, 42 liters of 30% alcohol solution will be needed.

And $70-42=28$ liters of 80% solution will be needed.