Quantitative Aptitude - Arithmetic Ability Questions

Prabhat has done 1/2 of a job in 12 days. Santosh completes the rest of the job in 6 days. In how many days can they together do the job?

Ifx4 + (1/x4) = 34, then what is the value of x3 – (1/x3)?

Choose the word which is least like the other words in the group.

A trader had 630 kgs of rice. He sold a part of it at 15% profit and the rest at 8% profit, so that he made a total profit of 12%. How much rice (in kgs) did he sell at 8% profit?

A rice trader buys 20 quintals of rice for Rs 8,580. However, 22% rice is lost in transportation. At what rate should he sell to earn 20% profit?

A race has three parts. The speed and time required to complete the individual parts for a runner is displayed on the following chart:
                       

                         Part I     Part II       Part III

Speed (kmph)       9            8              7.5

Time (minutes)     50          80             100

In a match of 50 overs, team A’s average runs for first thirty overs was 4.5 runs/over while for the remaining 20 overs the average was 5.5 runs/over. Team B chased the target and lost by 10 runs. Find the average runs per over scored by team B. (team B played all the 50 overs). 

If tan2A - sin2A = x, then value of x is