What is x when 31 divided by x equals 13?

To find the answer, just divide the dividend by the quotient: 31 ÷ 13 = 2.3846153846154

To prove this, let's compute 31 divided by 2.3846153846154: $\frac{31}{2.3846153846154} = 13$

How does it work?

Asking what the value of x could be when 31 divided by x gives a result of 13, is equivalent to solving the following equation:

$\frac{31}{x} = 13$

Multiply both sides by x: $\frac{31 x}{x} = 13 x$
$\frac{31 x}{x}$ is equivalent to $\frac{x}{x} \times 31$ , which simplifies to $1 \times 31$ (or just $31$ ).
Thus, the equation becomes: $31 = 13 x$
To find x, divide both sides by 13: $\frac{31}{13} = \frac{13 x}{13}$
Which gives, after simplification: $2.3846153846154 = x$ (or $x = 2.3846153846154$ )

So, if the dividend is 31 and the quotient is 13, the divisor is 2.3846153846154.