Question

In what ratio should three varieties of chemical A, B and C at the rate Rs. 120, Rs. 144 and Rs. 174 per litre be mixed to come up with a mixture worth Rs. 141 per litre?

• A. 1: 2: 3
• B. 11: 7: 77
• C. 11: 77: 7
• D. 11: 7: 1

Answer 1

The correct option is C 11: 77: 7

First mix varieties $A\&C$ in a ratio to get a mixture at the cost Rs. 141 per litre.

Applying Alligation:

Now mix varieties $A\&B$ to get a mixture at the cost of Rs. 141 per litre.

So, A: C in ratio 11: 7 and A: B in ratio 1: 7.The required ratio A: B: C = 11: 77: 7. Hence option (c).

2nd method:- By, observation, 141 is nearest to B (144) then A(120) and then C(174). When we mix all three then highest contribution will be according the above, i.e $B\to A\to C$ , Now only option (c).