Quantitative Aptitude - Arithmetic Ability Questions

A can do a work in 15 days and B in 20 days. If they work on it together for 5 days, then what fraction of work is left?

If Gangadhar's salary is 3/11 times of Hari's and Shambhu's is 3/4 times of Hari's, what is the ratio of Gangadhar's salary to Shambhu's?

If x - 1/x = 1 then what is the value of 1x1x-1-1x+1+1x2+1-1x2-1?

What is the value of (1/√2) Cot 45° + (1/√3) Cosec 60°?

The mean of 20 observations is 19. One more observation is included and the new mean becomes 20. The 21st observation is

A table tennis player, lost 12 games out of 18 games played. Calculate the games won in terms of decimal.

If cos ­-11π/6 = x, then the value of x is

The length of the diagonal of a square is 12 cm. Find its area (in cm2).