Answer:
The ratio of white:milk:dark is 9:8:4
Explantion:
Let w represent white chocolate , m represent milk chocolate and d represent dark chocolate
The ratio of white to not white is 3:4
Here not white means , it can be milk or dark chocolate
Then
w : (m+d) = 3:4
-----------------------------(1)
The ratio of not dark to dark is 17:4.
Again not dark means , it will be white or milk chocolate
Then,
(w+m) : d = 17:4 -----------------------------(2)
Representing (1) in fractions
![\frac{w}{m+d} =\frac{3}{4}](https://tex.z-dn.net/?f=%5Cfrac%7Bw%7D%7Bm%2Bd%7D%20%3D%5Cfrac%7B3%7D%7B4%7D)
4w = 3(m+d)
4w = 3m +3d
4w -3m =3d------------------------------(3)
Representing (2) in fractions
![\frac{(w+m)}{d}= \frac{17}{4}](https://tex.z-dn.net/?f=%5Cfrac%7B%28w%2Bm%29%7D%7Bd%7D%3D%20%5Cfrac%7B17%7D%7B4%7D)
4(w+m) = 17d
4w +4m = 17d---------------------------(4)
Subtracting (3) from (4)
4w +4m = 17d
4w -3m = 3d
(-)
-------------------------------
7m = 14d
-------------------------------
![\frac{m}{d} = \frac{14}{7}](https://tex.z-dn.net/?f=%5Cfrac%7Bm%7D%7Bd%7D%20%3D%20%5Cfrac%7B14%7D%7B7%7D)
![\frac{m}{d} = \frac{2}{1}](https://tex.z-dn.net/?f=%5Cfrac%7Bm%7D%7Bd%7D%20%3D%20%5Cfrac%7B2%7D%7B1%7D)
m:d = 2:1
Since w:(m+d)=3:4 let's make m:d a multiple of 4.
m:d = 8:4
w : (m+d) = 3:4 = 9:12
w:m:d = 9:8:4