A merchant has 1000 kg of sugar, part of which he sells at 8% profit and the rest at 18% profit. He gains 14% on the whole. The quantity sold at 18% profit is

Let the sugar sold at 8% gain = P
∴ Sugar sold at 18% gain = (1000 - P)
Let CP of sugar = ₹ Q per kg
Total CP = ₹ 1000 x Q
∴ [(108/100) x PQ)] + [(118/100) x (1000 - P) x Q]
= (114/100) x 1000 Q
⇒ 108PQ + 118000Q - 118PQ = 114000Q
⇒ 10P = 4000
∴ P = 400
∴ Quantity sold at 18% profit = 1000 - 400 = 600 kg