Quantitative Aptitude - Arithmetic Ability Questions

From the top of a 20 m high building, the angle of elevation of the top of a tower is 60° and the angle of depression of it's foot is at 45°, then the height of the tower is (√3=1.732)

The third proportional of the following numbers (x - ­y)2, (x2 - y2)2 is

What is the sum of the first 11 terms of an arithmetic progression if the first term is -31 and last term is 29?

Ram and Rahim standing at a distance of 680m run towards each other at a speed of 8 m/sec and 9 m/sec respectively. After how long will they meet?

A sum of money of Rs. 1000 is lent out in two parts in such a way that the interest on one part at 10% per annum for 5 years is equal to another at 5% for 10 years. Calculate the sum lent out at 5%.

A number when divided by the sum of 555 and 445 gives two times their difference as quotient and 30 as the remainder. The number is

ΔPQR has sides PQ and PR measuring 983 and 893 units respectively. How many such triangles are possible with all integral sides?

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?