Question 143892
How much pure water must be mixed with 6 pints of 90% developer to produce a mixture that is 17% developer?
----------------
active ingredient + active ingredient = active ingredient
0.9*6     +    0*x = 0.17(6+x)
5.4 = 1.02 + 0.17x
4.38 = 0.17x 
x = 25.76 pints ( pure water must be mixed with the 90% developer)
==========================
Cheers,
Stan H.