A boat travel 240 km downstream in 3 hours and the time is taken by the boat to travel the same distance in upstream in 6 hours. Find the speed of stream (in kmph).

If x cos²30⁰. sin60⁰=$${tan^2{45}^0.sec60^0}\over cosec\ 60^0$$ then the value of x : 

Rahul, Shyam and Rohan invested capital in the ratio of 2:3:4 for the time period of 6:4:3. Find the ratio of profit distributed?

 $${a\over b}={2\over3}$$ and $${b\over c}={4\over5}$$ then the ratio  $${a+b}\over {b+c}$$ equal to:

Two guns were fired from the same place at an interval of 13 minutes but a person in a train approaching the place hears the second shot 12 minutes 30 seconds after the first. Find the speed of train if sound travels at 330 metres per second.

Directions-Study the following diagram and answer the four questions.

The range of marks obtained by maximum no. of students is

If $$ {(2x-5y)^{3}-(2x+5y)^{3}=y{[A{x}^{2}+B{y}^{2}]}}$$, then what is the value of $$ {(2A-B)}$$?

In what time will ₹ 64,000 amount to ₹ 68,921 at 5 % per annum interest being compounded half yearly?