Question

A shopkeeper sells a Bulb to Nirmal earns 40% profit on it. Nirmal sells the Bulb to kamlesh at Rs. 630 at a loss of 10%. What is the cost price of the bulb?
1. Rs. 300
2. Rs. 500
3. Rs. 700
4. Rs. 900
5. Rs. 100

Answer 1

Correct Answer - Option 2 : Rs. 500

Given:  

Profit of Shopkeeper = 40%

Selling price of bulb for Nirmal = Rs. 630

Loss of Nirmal = 10%

Formula Used:

Cost price × (100 + Profit %)/100 = Selling price

Cost price × (100 – Loss %)/100 = Selling price

Calculation:

Cost price of bulb for Nirmal = Selling Price of bulb for Shopkeeper

⇒ Cost price of bulb for Nirmal = (630 × 100)/(100 – 10) = Rs. 700

Selling Price of bulb for Shopkeeper = Rs. 700

⇒ Cost price of bulb for shopkeeper = (700 × 100)/(100 + 40) = Rs. 500

∴ Cost price of the bulb is Rs. 500.