What is x when 13 divided by x equals 4?

To find the answer, just divide the dividend by the quotient: 13 ÷ 4 = 3.25

To prove this, let's compute 13 divided by 3.25: $\frac{13}{3.25} = 4$

How does it work?

Asking what the value of x could be when 13 divided by x gives a result of 4, is equivalent to solving the following equation:

$\frac{13}{x} = 4$

Multiply both sides by x: $\frac{13 x}{x} = 4 x$
$\frac{13 x}{x}$ is equivalent to $\frac{x}{x} \times 13$ , which simplifies to $1 \times 13$ (or just $13$ ).
Thus, the equation becomes: $13 = 4 x$
To find x, divide both sides by 4: $\frac{13}{4} = \frac{4 x}{4}$
Which gives, after simplification: $3.25 = x$ (or $x = 3.25$ )

So, if the dividend is 13 and the quotient is 4, the divisor is 3.25.