Quantitative Aptitude - Arithmetic Ability Questions

Which of the following quadratic equations has real roots?

A, B and C can finish a job working alone in 20, 30 and 60 days respectively. They all work together for 1 day, then A and B quit. How many days C working alone will take to finish the remaining part of the job?

A mason can build a wall in 18 hours. After 9 hours he takes a break. What fraction of the wall is yet to be built?

Given: x -­ 5 ≤ 2x -­ 3 and 2x - ­1/2 ≥ 5x + 2; then x can take which of the following values?

Tanya got an increment of 15% in her salary. If her enhanced salary is Rs.14,030. What was her original salary?

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

If (1 -­ cosA)/(1 + cosA) = x, then the value of x is

If 40 is 0.05% of x, then what is the value of x?