Quantitative Aptitude - Arithmetic Ability Questions

At a telephone exchange, three phones ring at intervals of 20 sec, 24 sec and 30 seconds. If they ring together at 11 : 25 a.m, when will they next ring together?

A ladder 20 m long is leaning against a vertical wall. It makes an angle of 30 deg with the ground. How high on the wall does the ladder reach?

For triangle ABC, find equation of median AD if co-ordinates of A, B and C are (-1,-3), (5,-4) and (3,2) respectively?

Find the odd word/letters/number pair from the given alternatives

What is the value of (cos 45 - 1/3) ?

In ΔPQR, S and T are points on side PQ and PR respectively. ST is parallel to QR. If S divides PQ in the ratio 4:1 and length of QR is 15 cm,what is the length of ST?

A sphere of radius 5 cm is melted to form a cone with base of same radius. The height (in cm) of the cone is

One of the two inlet pipes works twice as efficiently as the other. The two, working alongside a drain pipe that can empty a cistern all by itself in 8 hours, can fill the empty cistern in 8 hours. How many hours will the less efficient inlet pipe take to fill the empty cistern by itself?