Quantitative Aptitude - Arithmetic Ability Questions

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 cricketer, whose bowling average was 12.4 runs/wicket takes 5 wickets for 22 runs in a match, thereby decreases his average by 0.4. The number of wickets, taken by him before this match was:

The mean of 10 observations is 17. One more observation is included and the new mean becomes 16. The 11th observation is

A train 110 metres long is running with a speed of 60 kmph . In what time will it pass a man who is running at 6 kmph in the direction opposite to that in which the train is going ?

1/3 part of a certain journey is covered with the speed of 25 km/hr, 1/2 part of the journey is covered with the speed of 45 km/hr and the remaining part covered with the speed of 37.5 km/hr. What is the average speed (in km/hr) for the whole journey?

5% more is gained by selling a watch for Rs. 350 than by selling it for Rs. 340. The cost price of the watch is

The sum of the ages of Rohit and Ankit is 78. Rohit's age is twice the age of Ankit. What is the age (in years) of Rohit?

If tanθ = 815, then 1-sinθ1+sinθ is