The prices of tea and coffee per kg were the same in june. In july the price of coffee shot up by 20% and that of tea dropped by 10%. if in july , a mixture containing equal quantities of tea and coffee costs 50/kg. how much did a kg of coffee cost in june ? Choose the correct choice.
A) 45	B) 40	C) 35	D) 47.61	E) 30

Rationale: let the price of tea and coffee be x per kg in june . price of tea in july = 1.2 x price of coffee in july = 0.9 x . in july the price of 1 / 2 kg ( 500 gm ) of tea and 1 / 2 kg ( 500 gm ) of coffee ( equal quantities ) = 50 1.2 x ( 1 / 2 ) + 0.9 x ( 1 / 2 ) = 50 = > x = 47.61 d
Answer: D