Question
Mina sold 25 lamps at a profit of 20%. If she had sold
all the lamps for Rs. 2500 more, her overall profit would have been 40%. What is the selling price of 18 lamps at 30% profit?Solution
 Let the cost price of each lamp be Rs. z.  Initial selling price of all lamps = 1.2 × 25 × z = Rs. 30z  According to the question, 30z + 2500 = 1.4 × 25z Or, 35z - 30z = 2500 Or, 5z = 2500 Or, z = 500 Therefore, the selling price of 18 lamps at 30% profit = 18 × 1.3z = Rs. 11700
More Profit and loss Questions
Match List I with List II