In what ratio water must be added to dilute honey costing Rs. 300 per litre so that the resulted syrup would be worth Rs. 250 per litre?
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → 1 : 5
Water costs Rs. 0 per litre, honey Rs. 300 per litre, and the mixture is worth Rs. 250 per litre. By the rule of alligation:
\( \displaystyle \frac{\text{Water}}{\text{Honey}}=\frac{300-250}{250-0} \)
\( \displaystyle =\frac{50}{250} \)
\( \displaystyle =\frac{1}{5} \)
So water must be added to honey in the ratio 1 : 5.
Shortcut: Check Option (1): 1 litre of water with 5 litres of honey costs \( 5\times 300=1500 \) for 6 litres, i.e. \( \frac{1500}{6}=250 \) per litre.