Since first second varieties are mixed in equal proportions, so their average price = Rs.(126+135)/2= Rs.130.50 So, Now the mixture is formed by mixing two varieties, one at Rs. 130.50 per kg and the other at say Rs. 'x' per kg in the ratio 2 : 2, i.e., 1 : 1. We have to find 'x'.   Cost of 1 kg tea of 1st kind         Cost of 1 kg tea of 2nd kind         x-153/22.50 = 1  => x - 153 = 22.50  => x=175.50.  Hence, price of the third variety = Rs.175.50 per kg.