In ms E's park 1/3 of the total birds were grey color while the rest were either black or white. The white birds were twice as many as the black birds. After Ms E bought another 8 white birds and 8 black birds. The ratio of the number of white birds to the number of grey birds became 3:2. How many black birds did Ms E have in the end?
All birds => x
Grey => x/3 or 3x/9
Black => 2x/9
White => 4x/9
Ratio W : G = 4 : 3 (Before 8 white birds were added)
New ratio => (4x/9 + 8) / (3x/9) = 3 / 2 x = 144
Black birds => 2x/9 + 8 = 40