The age of a man is four times the sum of the ages of his two sons and after 10 years, his age will be double the sum of their ages. The present age of the man must be

If $\sqrt{\frac{1}{25}} = 1 + \frac{x}{144}$, then $x$ is

If $\frac{3}{x+y} + \frac{2}{x-y} = -1$ and $\frac{1}{x+y} - \frac{1}{x-y} = \frac{4}{3}$ then $(x, y)$ is:

$\frac{2x+5}{10} + \frac{3x+10}{15} = 5$, find $x$

Find value of $x^2 - 10x + 1$ if $x = \frac{1}{5-2\sqrt{6}}$

In a multiple choice question paper consisting of $100$ questions of $1$ mark each, a candidate gets $60\%$ marks. If the candidate attempted all questions and there was a penalty of $0.25$ marks for wrong answers is:

The solution of the following system of linear eqs. $2x - 5y + 4 = 0$ and $2x + y - 8 = 0$ will be: