Question
A jar contains a mixture of two types of oil, A and B.
Oil A costs Rs 60 per litre and oil B costs Rs 90 per litre. In what ratio should A and B be mixed so that the mixture costs Rs 72 per litre?Solution
ATQ, Use alligation: Cheaper (A): 60 Dearer (B): 90 Mean price: 72 Ratio (Quantity of A : Quantity of B) = (90 − 72) : (72 − 60) = 18 : 12 = 3 : 2 So A : B = 3 : 2.
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