$A$ man completes $\frac{2}{15}$ of his journey by aeroplane,$\frac{2}{5}$ by train and the rest by taxi. What part of his journey does he complete by taxi?

The value of $\frac{2.75 \times 2.75 \times 2.75 - 2.25 \times 2.25 \times 2.25}{2.75 \times 2.75 + 2.75 \times 2.25 + 2.25 \times 2.25}$ is:

Each member of a club contributes as many rupees and as many paise as the number of members of the club. If the total contribution is $Rs. 2525$,then the number of members of the club is:

If $x = \sqrt{a \sqrt[3]{b \sqrt{a \sqrt[3]{b \dots \infty}}}},$ then the value of $x$ is:

$A$ boy was asked to multiply a given number by $\frac{8}{17}$. Instead,he divided it by $\frac{8}{17}$ and got the result $225$ more than what he should have got if he had multiplied the number by $\frac{8}{17}$. The given number was:

$\frac{4.2 \times 4.2 - 1.9 \times 1.9}{2.3 \times 6.1} = ?$