If $$ {x+{1\over x}}=3$$ then find the value of $$ {x^2}-{1\over {x^2}}$$:

If $$ \sqrt{0.04×0.4×a} =0.4×0.04×{\sqrt{b}}$$ then the value of $$ {a\over b}$$ is:

The value of $$ {4^{10+n}}.{16^{3n-4}}\over4^{7n}$$ is:

Find the value of ∠x in the given figure.

 In the given figure, BO and CO are the bisector of ∠CBD and ∠BCE respectively ∠A=40°, then ∠BOC is equal to:

If 80 Persons can finish a work in 16 days by working 6 hours a day, the number of hours a day should 64 persons work to finish that same job in 15 days is:

A shopkeeper offers 10% discount on every   purchase of an article. It also offers an additional discount of 12%. If the payment is made in cash. If the original price of an item is Rs. 250, how  much a customer will pay. If he wants to pay the price in cash?

The current ages of Sonali and Monali are in the ratio 5:3. Five years from now, their ages will be in the ratio 10:7 Then, Monali’s current age is: