A right triangle with sides 5 cm, 12 cm and   13 cm is rotated about the side 12 cm to from a cone. The volume of the cone so formed is :

Table below shows the number of candidates appearing for the interview and the percentage of candidates found eligible for the post in various companies (A, B, C, D, E, F).
Study the Tables and give answer the following Questions.

What is the respective ratio between the number of qualified candidates in Company A and the number of candidates qualified in Company E?

The ratio of present ages of Ratna and Shantanu is 5:4. After 19 years, the ratio of their ages will be 10:9. What is Ratna's present age?

Direction: what should come in place at question mark(?).

$$ {4\over 7}×{2{4\over 5}÷{2\over 5}=?}$$

A can finish work in 18 days and B in 36 days. If they work on it together for 9 days, what percent of work is left?

If the sum of the squares of three consecutive natural numbers is 110, then the smallest of these natural numbers is:

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

A boat can row 15 km per hour downstream and 9 km per hour upstream. The speed (in km/hour) of the boat in still water is: