Quantitative Aptitude - Arithmetic Ability Questions

In the following question, select the odd word from the given alternatives.

If a + b = 11 and a2+ b2= 61, then value of ab is

The simple interest accrued on a sum of money at the end of four years is 1/5th of its principal. What is the rate of interest per annum?

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?

PQ is the chord of a circle whose centre is O. ROS is a line segment originating from a point R on the circle that intersect PQ produced at point S such that QS = OR. If ∠QSR = 30°, then what is the value (in degrees)of POR?

If the product of two numbers is 3026 and their LCM is 89, then their HCF is :

A boy starts from his house and walks at a speed of 5 km/hr and reaches his school 3 minutes late. Next day he starts at the same time and increases hisspeed by 4 km/hr and reaches 3 minutes early. What is the distance (in km) between the school and his house?

The average weight of 35 apples is 50 grams. If some apples of weight 40 grams each were removed, then average weight becomes 57.5 grams. How many apples of weight 40 grams were removed?