Two varieties of Coffee worth Rs. 126 per kg and Rs. 130 per kg are mixed with a third variety in the ratio 1: 1: 2. If the resulting mixture is worth Rs. 172 per kg, then find the price (Rs. /kg) of the third variety of the coffee.
Soln:
Two varieties @ Rs. 126 and Rs. 130 are mixed in equal ratio of 1: 1. So, their average price can be taken as (126+130)2=Rs. 128 per kg. Now we have two varieties: one at the rate Rs. 128 per kg and other at the rate Rs. x per kg which are mixed in the ratio 2: 2 or 1: 1 to give a resulting mixture of Rs. 172 per kg.
Applying Alligation:
X−17244=11
x = 216.
So, the price of the third variant is Rs. 216 per kg. Hence option (a)