The ratio in which a grocer must mix two varieties of tea worth Rs. 60 per kg and Rs. 65 per kg so that by selling the mixture at Rs. 68.20 per kg he may gain 10% is:
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → 3 : 2
The selling price includes a 10% gain, so the cost price of the mixture is
\( \displaystyle \frac{68.20}{1.1} = 62 \text{ per kg} \)
By the rule of alligation, the quantities of the cheaper and the dearer tea are in the ratio
\((\text{dearer} - \text{mean}) : (\text{mean} - \text{cheaper})\)
\(= (65 - 62) : (62 - 60) = 3 : 2\)
So the Rs. 60 tea and the Rs. 65 tea are mixed in the ratio 3 : 2.