A shopkeeper has 100 kg of apples. He sells 50% of these at 25% profit and remaining 50% at 30% profit. Find his % profit on total. Pick one:
A) 27.5 %
B) 25.6 %
C) 31.5 %
D) 35.9 %
E) 29.5 %

Rationale: "total number of apples = 100 let the cost price be x selling price at 25 % profit = 1.25 x selling price at 30 % profit = 1.3 x profit % = ( ( sp - cp ) / cp ) * 100 profit % = ( ( 1 / 2 ) * 100 * 1.25 x + ( 1 / 2 ) * 100 * 1.3 x - 100 x ) / 100 x * 100 = ( 255 - 200 ) / 2 = 27.5 % answer is a"
Answer: A