एक विक्रेता 3 रुपये में 15 नींबू बेचता है जिससे उसे 60% का लाभ होता है। उसने एक रुपये में कितने नींबू खरीदे थे?

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?