Quantitative Aptitude - Arithmetic Ability Questions

A water tank is 2/5 th full. Inlet A can fill the tank in 12 minutes while an outlet pipe B can empty it in 6minutes. If both the pipes are open, how long will it take to empty or fill the tank completely?

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

If 2+aa + 2+bb + 2+cc = 4, then the value of ab+bc+caabc is

Hiten marks his pen at Rs 9800 and after allowing discount of 20%, he still earns 12% profit. What is the cost price (in Rs) of the pen?

If a + b = 4 and ab = -5, then what is the value of a3 + b3?

What should be added to 5(2x-y) to obtain 4(2x - 3y) + 5(x + 4y)?

If a(x + y) = b(x - y) = 2ab, then the value of 2(x2 + y2)

Which one is the largest among the fractions (5/113), (7/120), (13/145) and (17/160)?