If each interior angle is doubled of each exterior angle of a regular polygon with n sides, then the value of n is 

In what time will the simple interest be $$ {2\over5} $$ of the principal at 8% per annum? 

A circle with radius 42 cm is drawn. What will be length of arc of a sector subtending an angle of 60 degrees at the Centre?

The value of $$ {tan\ 40°+tan\ 20° +\sqrt{3}\ tan20° tan40°}$$?

Mr. Mike borrowed Rs. 8500 at 4 % per annum compound interest. The compound interest compounded annually for 2 yeas is:

What is the slope of the line perpendicular to the line passing through the points (-5, 1) and (-2, 0)? 

The following table shows the number of pens and the number of erasers of 6 different colours that were sold from a stationery store during a given week. 

The total number of erasers having colours C3 or C4 is approximately what percentage of the average number of pens of each colour?

A is twice as fast as B and B is thrice as fast as C. The Journey covered by C in  42 minutes will be covered by A in.