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:

600 kg

      Total quantity                   At 18% profit

     2 + 3    = 5                            3

                   ↓                            ↓

                ×200                        ×200

                    ↓                           ↓

           1000 (Given)                   600Kg