Quantitative Aptitude - Arithmetic Ability Questions

If cot ­-4π/3 = x, then the value of x is

What is the value of (cos 45 - 1/3) ?

A boat covers a distance of 14 km upstream and 16 km downstream in 9 hours. It covers a distance of 12 km upstream and 40 km downstream in 11hours. What is the speed (in km/hr) of the boat in still water?

Given: 6x + 2(6-x) > 2x -2 < 5x/2 - 3x/4; then x can take which of the following values?

A's salary was decreased by 50% and subsequently increased by 50%. How much percent does he lose?

AB is the diameter of a circle with center O and P be a point on its circumference. If ∡POA = 120°, then the value of ∡PBO is

A box consist of 5 rupees, 2 rupees and 1 rupee coins and their value are in the ratio of 15 : 4 : 2 respectively. If there are total 112 coins, then how many 2 rupees coins are there in the box?

If x -­ y = ­7 and x + y = 13, then x2 - y2 is