How many kilograms of sugar costing Rs. 9 per kg must be mixed with 27 kg of sugar costing Rs. 7 per Kg so that there may be a gain of 10 % by selling the mixture at Rs. 9.24 per Kg ?	Choose the correct choice:	A) 83 Kg	B) 65 Kg	C) 13 Kg	D) 63 Kg	E) 23 Kg
By the rule of alligation:   C.P. of 1 kg sugar of 1st kind C.P. of 1 kg sugar of 2nd kind   Ratio of quantities of 1st and 2nd kind = 14 : 6 = 7 : 3.   Let x kg of sugar of 1st kind be mixed with 27 kg of 2nd kind.   Then, 7 : 3 = x : 27 or x = (7 x 27 / 3) = 63 kg.   Answer: 63 Kg
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How many kilograms of sugar costing Rs. 9 per kg must be mixed with 27 kg of sugar costing Rs. 7 per Kg so that there may be a gain of 10 % by selling the mixture at Rs. 9.24 per Kg ?