Quantitative Aptitude - Arithmetic Ability Questions

A helicopter, at an altitude of 1500 m, finds that two ships are sailing towards it, in the same direction. The angles of depression of the ships as observed from the helicopter are 60° and 30°respectively. Distance between the two ships, in metres is

If the amount received at the end of 2nd and 3rd year at compound interest on a certain Principal is Rs 30250, and Rs 33275 respectively, what is the rate of interest?

Two pipes X and Y can fill an empty tank in 16 hours and 20 hours respectively. Pipe Z alone can empty the completely filled tank in 25 hours. Firstly both pipes X and Y are opened and after 6 hours pipe Z is also opened. What will be the total time (in hours) taken to completely fill the tank?

Robin can do a work in 10 hours. Pradeep and Robin together can do the same work in 4 hours. Pradeep and Nitin together can do the samework in 5 hours. In how many hours Nitin alone can complete the same work?

An alloy contains copper and tin in the ratio 3 : 2. If 250 gm of copper is added to this alloy then the copper in it becomes double the quantity of tin in it. What is the amount (in gm) of tin in the alloy?

If a - b = 1 and ab = 6, then what is the value of a3- b3?

What is the value of tan 7π/6?

Marked price of an item is Rs 900. On purchase of 2 items discount is 6%, on purchase of 3 items discount is 12%. Rajani buys 5 items, what is the effective discount?