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Question

The cost price of 10 articles is equal to the selling price of 9 articles. Find the percentage profit.

This question was previously asked in
RRB NTPC 2019 CBT 1 Question Paper (8-Mar-2021) (Shift 2)
The correct answer is
$11 \frac{1}{9} \%$

Calculating Profit Percentage

The problem states that the cost price (CP) of 10 articles is equal to the selling price (SP) of 9 articles. We need to find the profit percentage.

Relating Cost Price and Selling Price

Let the cost price of one article be CP and the selling price of one article be SP.

According to the question:

$ 10 \times \text{CP} = 9 \times \text{SP} $

From this equation, we can express the cost price in terms of the selling price:

$ \text{CP} = \frac{9}{10} \times \text{SP} $

Calculating Profit

Since the cost price ($\frac{9}{10} \times \text{SP}$) is less than the selling price (SP), there is a profit.

Profit = Selling Price - Cost Price

Profit = $ \text{SP} - \text{CP} $

Substitute the value of CP:

Profit = $ \text{SP} - \left( \frac{9}{10} \times \text{SP} \right) $

Profit = $ \left( 1 - \frac{9}{10} \right) \times \text{SP} $

Profit = $ \frac{1}{10} \times \text{SP} $

Calculating Profit Percentage

The formula for profit percentage is:

Profit % = $ \left( \frac{\text{Profit}}{\text{CP}} \right) \times 100\% $

Substitute the values for Profit and CP:

Profit % = $ \left( \frac{\frac{1}{10} \times \text{SP}}{\frac{9}{10} \times \text{SP}} \right) \times 100\% $

Simplify the expression:

Profit % = $ \left( \frac{1}{9} \right) \times 100\% $

Profit % = $ \frac{100}{9} \% $

Convert the improper fraction to a mixed number:

Profit % = $ 11 \frac{1}{9} \% $

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Similar Questions

  1. I bought two frocks for ₹1,200. I sold the first one at a loss of 7% and the second at a gain of 23%. If, on the whole I made neither a loss nor a gain, find the cost price (in ₹) of the first frock.
  2. The selling price of 40 books is equal to the cost price of 28 books. Find the loss or gain percentage.
  3. I bought two toy guns for ₹1,200. I sold the first one at a loss of 8% and the second at a gain of 16%. If, on the whole I made neither a loss nor a gain, find the cost price (in ₹) of the first toy gun.
  4. By selling $50$ mangoes for $₹30$, a person loses $10\%$. How many mangoes should he sell for $₹28$ to gain $20\%$?
  5. Sarita buys two old Samsung and three Mi mobile phones for ₹40,200. If she sells the Samsung phones at a 10% profit and the Mi phones at a 20% profit then her total profit is ₹5,640. The cost price of the Mi phone is:
  6. The cost price of 19 pens is equal to the selling price of 16 pens. Percentage gain is:
  7. X purchased a car at ₹ 1,50,000 and then sold it to Y at a profit of 5%. Y later sold it back to X at a loss of 2%. Find the overall profit or loss for X in the entire transaction
  8. The cost price of a car was ₹1,50,000. It was sold by X at a profit of 5% to Y. It was later sold back to X by Y at a 1% loss. Find X's profit in the entire transaction.
  9. A vendor sells 10 oranges for ₹1 and gains $30\%$. How many oranges did he buy for ₹1?
  10. Sohan lost $20\%$ by selling his old fan for ₹1,500. At what price (in ₹) he should have sold it to get $20\%$ profit?

Important Questions from Profit and Loss

  1. By selling an article for Rs. 2,200, a profit of 10% is earned. If the same article is sold for Rs. 2,600, then what will be the gain percentage?

  2. By selling an article for Rs. 640, a person loses 15% of its selling price. At what price (in Rs.) should he sell it to gain 15% on its cost price?

  3. The selling prices of articles A and B are the same. A is sold at a profit of 28 percent and B is sold at a loss of 24 percent. If the total selling price of the both articles is Rs. 48640, then what is the cost price of A and B, respectively ?

  4. The cost price of an article is Rs. 2800. Profit as a percentage of selling price is 20 percent. What is the actual profit (in Rs.) ?

  5. A trader bought 640 kg of rice. He sold a part of rice at 20% profit and the rest at 5% loss. He earned a profit of 15% in the entire transaction. What is the quantity (in kg) of rice that he sold at 5% loss?

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