Quantitative Aptitude - Arithmetic Ability Questions

Of the 3 numbers whose average is 70, the first is 1/9 times the sum of other 2. The first number is

Three clocks are designed to alarm in every hour, two hours and three hours respectively. If they all alrmed together three hours before, then after how many hours will they next alarm together?

What is the area (in square units) of the figure enclosed by the graphs of the lines x = -4, x = 2, y = -2 and y = 3?

If 2x/3 - [5(4x/5 - 4/3)]/2 = 1/3, then what is the value of x?

The value of x13+x-13x23-1+x-23

Coefficient of x2 in (x + 9)(6 -­ 4x) is

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 ?