Average age of x students in a group is 20. When 4 new students are admitted with a age of 7.5 years each, then the average is decreased by 5. What is the value of x?

If 80 Persons can finish a work in 16 days by working 6 hours a day, the number of hours a day should 64 persons work to finish that same job in 15 days is:

What is the area (in cm²) of the circumcircle of a triangle whose sides are 6 cm, 8 cm and 10 cm respectively?

The principal which gives ₹ 1 interest per day at a rate of 5 % simple interest per annum is 

The LCM of two positive integers is twice the larger number and the HCF of the two numbers is 3. The smaller number is:

Value of $$ \sqrt{6+\sqrt {6+\sqrt {6+....}}}$$

A wholesaler purchased 7 hair clips for a rupee. How many for a rupee must he sell to get profit of 40%?

The top of two poles of height 24m and 36 m are connected by a wire. If the wire makes an angle of 60° with the horizontal, then the length of the wire is