Quantitative Aptitude - Arithmetic Ability Questions

In the following question, select the odd number group from the given alternatives.

If a - b = 3 and a2+b2=25, then the value of ab is

Two donkeys are standing 400 meters apart. First donkey can run at a speed of 3 m/sec and the second can run at 2 m/sec. If two donkeys run towards each other after how much time (in sec) will they bump into each other?

An equilateral triangle ABC is inscribed in a circle of radius 20√3.
The centroid of the triangle ABC is at a distance d from the vertex A. What is d equal to ?

The radius of the circle circumscribing the three vertices of an equilateral triangle is 12 cm. Determine the height (in cm) of the equilateral triangle

If 3x + 4(1-x) > 5x -2 > 3x - 4; then the value of x is

Rohit buys a ball for Rs 450 and sells it. Rohit gives two successive discount of 20% and 5% to the customer. What will be the selling price (in Rs) of the ball?

Select the odd letters from the given alternatives.