Well, y=ny
2(y-1)=ny
(where ny is not-yellow)
You get y=2y-2 or y=2. You had two yellow birds and two other types.
Answer: Space was alloted for each subject is 8 dm, 8 dm, 12 dm.
Explanation:
Since we have given the length of bulletin board =28 dm
Let the share of three subject areas be 2x,2x,3x
According to question,

so x=4 dm
Now,
Space was alloted for each subject is given as below:
First subject =
Second subject =
Third subject =
<span>4x – 20 = 900
4x = 900+20
4x = 920
x = 920/4
x = 230
he earned $230
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