The population of a city is 320000. If the annual birth rate is 9.2% and the annual death rate is 1.7%, calculate the population of the town after 3 years.

The cost of a car, purchased 2 years ago, depreciates at the rate of 20% every year. If its present worth is ₹315600, find :

(i) its purchase price

(ii) its value after 3 years.

Amar Singh started a business with an initial investment of ₹400000. In the first year, he incurred a loss of 4%. However, during the second year, he earned a profit of 5% which in third year rose to 10%. Calculate his net profit for the entire period of 3 years.