Solution -
The ratio of Dew and Sprite in Mixture(M1) = 7 : 3
Dew in mixture(M1) = 7/10
The ratio of Dew and Sprite in Mixture(M2) = 5 : 4
Dew in mixture(M2) = 5/9
The ratio of new mixture = 2 : 1
Dew in new mixture = 2/3 (required)
Required ratio = [(2/3) - (5/9)] / [(7/10) - (2/3)]
= [1/9] / [1/30]
= 30/9
= 10/3
= 10 : 3
Therefore,
The required ratio is 10 : 3.
Hence,
The correct answer is option (a) 10 : 3.
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