Quantitative Aptitude - Arithmetic Ability Questions

If the numbers  93, 204, 256 are arranged in ascending order, then the right arrangement is 

If x + (1/x) = √13, then what is the value of x5 – (1/x5)?

What is the value of tan 7π/6?

If 3x + 5y + 7z = 49 and 9x + 8y + 21z = 126, then what is the value of y?

If the amount received at the end of 2nd and 3rd year at compound interest on a certain Principal is Rs 30250, and Rs 33275 respectively, what is the rate of interest?

The area of a square is 40.5 cm². Find the length of its diagonal (in cm).

Dalajit lent Rs 10800 to Jaabir for 3 years and Rs 7500 to Kabir for 2 years on simple interest at the same rate of interest and received Rs 1422 in all from both of them as interest. The rate of interest per annum is

Robin can do a work in 10 hours. Pradeep and Robin together can do the same work in 4 hours. Pradeep and Nitin together can do the samework in 5 hours. In how many hours Nitin alone can complete the same work?