Quantitative Aptitude - Arithmetic Ability Questions

An equilateral triangle of area 300 cm2 is cut from its three vertices to form a regular hexagon. Area of hexagon is what percent of the area of triangle?

There are two numbers such that the first number is half of the second number. If their average is 57, then what is the first number?

Pipe A can empty a filled tank in 28 hours while Pipe B can fill the same tank, when empty in 35 hrs. If alternatively Pipes A and B are turned on for an hour each time, starting when the tank is full, how long will it take to empty the tank?

The ratio of cost price and selling price 25:26. The percent of profit will be

∆DEF is right angled at E. If m∠F = 45°, then find the value of (cosecD - 1/√3).

The lengths of the two diagonals of a rhombus are 5 cm and 12 cm. Find its area (in cm2)

Working together, pipes A and B can fill an empty tank in 10 hours. They worked together for 4 hours and then B stopped and A continued filling the tank till it was full. It took a total of 13 hours to fill the tank. How long would it take A to fill the empty tank alone?

P does half as much work as Q in 1/3 of the time. If together they take 15 days to complete a work, how many days will P take to do it alone?