Question
In a 150-liter mixture, the ratio of petrol to diesel is
4:1. To obtain a final mixture with 25% diesel, how much diesel needs to be added to the existing mixture?Solution
ATQ, Quantity of petrol in the original mixture = 150 × (4/5) = 120 liters Percentage of petrol in the new mixture = 100% - 25% = 75% Total quantity of mixture that contains 75% petrol = 120 ÷ 0.75 = 160 liters So, quantity of diesel to be added = 160 - 150 = 10 liters
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