If X persons are admitted in a hospital during the last five years and Y persons are recovered out of them during this period then find the average number of persons admitted in one year:

There are 45 persons staying at a hostel. The average expenses of a person for a day are rupees 20. The total expenses for all the persons for a week are:

The average earning of a shop for first three weeks of a month are 2750 per week. If the earnings of next 2 weeks are 4750 rupees then find total earnings of the 5 weeks.

The average height of a class of 18 students is 105 cm. After the arrival of 7 new students the average decreases by 5cm. Find sum of the heights of all the students in the class.