A man sells a mobile phone for ₹600 and loses a certain amount. If he had sold it for ₹1,200, his gain would have been 2 times the former loss. The cost price (in ₹) of the mobile phone is _______.

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?