The value of $0.008 \times 0.01 \times 0.0072 \div (0.12 \times 0.0004)$ is

If $(\frac{5}{9} \text{ of } x) - (\frac{2}{5} \text{ of } \frac{9}{4}) = -\frac{4}{5}$,then find $x$.

Find the value of the following expression up to four places of decimals:
$\left[1+\frac{1}{1 \times 2}+\frac{1}{1 \times 2 \times 4}+\frac{1}{1 \times 2 \times 4 \times 8}+\frac{1}{1 \times 2 \times 4 \times 8 \times 16}\right]$

$4^{11} + 4^{12} + 4^{13} + 4^{14}$ is divisible by:

$A$ 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:

The difference between $1 \frac{3}{16}$ and its reciprocal is: