A saree store declares a discount scheme: 'Buy 1 saree and get 75% off on another saree of the same price'. What is the profit percentage of the store on selling a pair of sarees, if each saree has a cost price 75% below the marked price?

A company considers hiring an extra machine for $150 per day to produce additional units. If the additional throughput contribution generated from producing these units on the machine is $390, by how much will total profit increase?

If the cost price of an article is 85 times its selling price, what is the loss percentage?