Correct Answer - Option 3 : Rs 175
Given
Salt worth = Rs 120 and Rs 130 per kg
Calculations :
Since, 1st and 2nd varieties are mixed in equal proportions.
So, their average price = (120 + 130)/ 2
= Rs. 125
So, the mixture formed by mixing two varieties, one at 125 Rs. per kg and the other at say x per kg in the 2 : 2, i.e, 1 : 1.
⇒(x - 150)/25 = 1
⇒ x = 175
∴ the cost of 3rd variety is Rs. 175 per kg.