Question 747959
The current non-juice volume is .9 x 2l or 1.8 l

A 25% mix means 1.8 = 75% of new mix and 2.4 is total volume.

.6l of juice total, but so far there's .2l juice, so add .4l juice. 

We go from .2/2 (10%) to .6/2.4 (25%)