Find the cost in rupees for carpeting a room 65dm× 30 dm at Rs. 45 per sq.m

Directions: The following table represents the percentage marks of four students in six subjects.
Consider the table and answer questions based on it

The average marks obtained by the students in Geography and History are

A boat moves downstream at the rate of 1 km in minutes and upstream at the rate of 5 km an hour. What is the speed of the boat in the still water?  

Find the forth proportional to , and .

The mean of the first 7 prime numbers is:

ΔPQR is right angled at Q. If cos P = 3/5, then what is the value of cos R?

A rectangular piece of paper of dimensions 22 cm by 12 cm is rolled along its length to form a cylinder. The volume (in cm³) of the cylinder so formed is 

What is the sum of two consecutive even numbers, the difference of whose square is 84?