Question 1204664
20% solution, 50 ml.  to  be made using 10% and 50% solutions.
How much of each?


20 is closer to 10 than it is to 50.  Most of the resulting solution will be from the 10% solution.


v of the 50%
50-v of the 10%
{{{50v+10(50-v)=20*50}}}



{{{50v-10v+10*50=20*50}}}

{{{(50-10)v=20*50-10*50}}}

{{{v=50((20-10)/(50-10))}}}---------See how the given values correspond.

{{{v=50(1/4)}}}

{{{v=12&1/2}}}----------the ml. of 50% solution to use.