Quantitative Aptitude - Arithmetic Ability Questions

In the given figure, PQRS is a square inscribed in a circle of radius 4 cm. PQ is produced till point Y. From Y a tangent is drawn to the circle at point R. What is the length (in cm) of SY ?

What is the average of first 19 odd numbers?

50% of a = b, then b% of 40 is the same as _________ of a.

Before a battle there were the ratio of captains to soldiers was 2 : 7. During the war 25 captains and 100 soldiers were martyred. The new ratio of captains to soldiers became 3 : 10. What is the number of soldiers after the war?

Simplify : 69 X 69 X 69 -65 X 65 X 669 X 69 + 69 X 65 + 65 X 65

Pannalal has done 1/3rd of a job in 20 days, Saiprasad completes the rest of the job in 10 days. In how many days can they together do the job?

If a person walks at 15 km/hr instead of 9 km/hr, he would have walked 3 km more in the same time. What is the actual distance (in kms) travelled by him? 

A vendor buys oranges at the rate of 5 for Rs 6 and sells at the rate of 2 for Rs 3. What will be the result?