What is x when 31 divided by x equals 39?

To find the answer, just divide the dividend by the quotient: 31 ÷ 39 = 0.79487179487179

To prove this, let's compute 31 divided by 0.79487179487179: $\frac{31}{0.79487179487179} = 39$

How does it work?

Asking what the value of x could be when 31 divided by x gives a result of 39, is equivalent to solving the following equation:

$\frac{31}{x} = 39$

Multiply both sides by x: $\frac{31 x}{x} = 39 x$
$\frac{31 x}{x}$ is equivalent to $\frac{x}{x} \times 31$ , which simplifies to $1 \times 31$ (or just $31$ ).
Thus, the equation becomes: $31 = 39 x$
To find x, divide both sides by 39: $\frac{31}{39} = \frac{39 x}{39}$
Which gives, after simplification: $0.79487179487179 = x$ (or $x = 0.79487179487179$ )

So, if the dividend is 31 and the quotient is 39, the divisor is 0.79487179487179.