Question 1037352
.
You need a 80% alcohol solution. On hand, you have a 25 mL of a 50% alcohol mixture. You also have 85% alcohol mixture. 
How much of the 85% mixture will you need to add to obtain the desired solution?
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


See the lesson <A HREF=https://www.algebra.com/algebra/homework/word/mixtures/Solving-typical-mixture-problems.lesson>Solving typical word problems on mixtures for solutions</A> in this site.


Similar problem was solved there (Problem 2).


It is your sample. Read it attentively,
and then solve your problem by substituting your data.