20 articles cost ₹ 100. What is the cost of 1 article ?

If 20 articles cost ₹180, the cost of 15 articles is:

If 40 articles cost Rs. 180, the cost of 18 articles is:

Cost price of article A is Rs 200 more than the cost price of article B. Article A was sold at 10% loss and article B was sold at 25% profit. If the overall profit earned after selling both the articles is 4%, then what is the cost price of article B?

Selling price of an article is र 2220 and the per cent profit earned is 20%. What is the cost price of the article?

An articles was sold for Rs. 760, which incured a loss of 5%. What is the cost price of the article ?

An article was sold for Rs 760, which incurred a loss of 5%. What is the cost price of the article?

If an article costs 25% less, a profit of ₹100 more can be made by selling the article at the usual price. What is the cost price of the article ?