The sum of two digit number is 16. If the digit is interchanged the number is formed 18 less than the original number. Find the original number.

The ratio of the incomes of two employees is 7 : 4, and the ratio of their expenditures is 3 : 1. If each of them manages to save ₹4,800 per month, find the sum of their monthly incomes (in ₹). 

The length of the diagonal and the breadth of a rectangle is 13 cm and 5 cm respectively. Calculate its area (in cm²).

If the cost of 10 books is ₹250, then find the cost of 15 books.

Ram sold an article for Rs 380 at some profit. Had he sold it for Rs 300, then there would have been a loss equal to one-third at the initial point. What was the cost price of the article? 

The measure of a cuboid warehouse is (8 m x 6 m x 3 m). If each sack covers 0.48 cubic meters of space, how many maximum sacks can be kept in it?

The population of a city in the year 2020 was 2,00,000. The rate of growth of population is 8% per annum. Find the population of that city in the year 2022.

If $$ {2^{2n-1}}={1\over8^{n-3}}$$,then the value of n is: