Quantitative Aptitude - Arithmetic Ability Questions

In these tests find the Odd figure out

When [x + (1/x)] = 5, then what is the value of [x – (1/x)]?

If [a + (1/a)]2 – 2[a – (1/a)] = 12, then which of the following is a value of 'a'?

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

A telephone bill costs Rs.13 for 19 minutes. What is the cost in rupees for 15 minutes 50 seconds?(rounded to one decimal)

The age of Rakhi is twelve times that of her daughter Anubha. If age of Anubha is 3 years now, then what was the age of Rakhi, 2 years earlier?

The first and last terms of an arithmetic progression are 29 and -49. If the sum of the series is -140, then it has how many terms?

Two circles are having radii 9 cm and 12 cm. The distance between their centres is 15 cm. What is the length (in cm) of their common chord?