Quantitative Aptitude - Arithmetic Ability Questions

Find the odd words/letter/number from the given alternatives:

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?

The value of (2+32-3-342) is

Find the median, mode and mean of 9, 5, 8, 9, 9, 7, 8, 9, 8.

What is that least number that must be added to the product 684 × 686 to make it a perfect square?

If x - y = -8 and xy = 45, then (x2 + y2) is

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

Which of the following quadratic equations has real roots?