Problema Solution
A solution of ethyl alcohol is 75% alcohol by weight is to be used as a bactericide. The solutions is to be made by adding water to a 95% ethyl alcohol solution. How many grams of each should be used to prepare 400 grams of the bactericide.
Answer provided by our tutors
Let
x = grams of water
y = grams of 95% ethyl alcohol
x + y = 400
0*x + 0.95*y = 0.75(x + y)
........
click here to see the system of equations solved for x and y
........
x = 84.21 g
y = 315.79 g
84.21 grams of water and 315.79 grams of 95% ethyl alcohol should be used.