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Mixture of whiskey and water = 66 liters
Initial ratio of whiskey and water = 4:7
Changed ratio of whiskey and water = 2:3
Let the whiskey be 4x
and water be 7x
A/q
4x+7x = 66
=> 11x = 66
=> x = 66/11 = 6
Whisky = 4×6 = 24 litres
Water = 7×6 = 42 litres
Now,
4+x/7+x = 2/3
=> 3(4+x) = 2(7+x)
=> 12 + 3x = 14 + 2x
=> 3x - 2x = 14 - 12
=> x = 2
Then,
Whisky = 4+x = 4+2 = 6
Water = 7+x = 7+2 = 9
So,
Whiskey = 6 × 6 = 36 litres
Water = 9×6 = 54 litres
Hence,
Initial weight of whiskey = 24 litres
Changed Weight of whiskey = 36 litres
Added Whiskey 36-21=12L
Initial weight of water = 42 litres
Changed Weight of water = 54 litres
Added Water-54-42=12 L
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