Profit and loss 34 - 10th grade

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A businessman reduced the price of his products 25% below marked price during
a sale, which had originally been fixed at 25% profit on cost price after deducting
10% discount for cash price. What percent does he gain or lose?

Solution: Firstly, we need to find the Marked Price.

When the cost price was $100, the first selling price was $125

So, the first Marked Price was ${(100/90) * 125} since 10% discount was allowed

Again, since the first Marked Price decreased by 25%

So, the new Marked Price = $ {(75/100) * (100/90) * 125} = $(625/6} = $104 ¹/₆

So, his profit = (104 ¹/₆ – 100) % = 4 ¹/₆ %