By selling rubber bands at the rate of 32 for a rupee, a man loses 40%. How many rubber bands for a rupee should he sell in order to gain 20%?

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?