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 one:	A) 36 Kg	B) 42 Kg	C) 54 Kg	D) 63 Kg	E) None of these
Solution   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
<result>D</result>
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?