What is x when 40 divided by x equals 13?

To find the answer, just divide the dividend by the quotient: 40 ÷ 13 = 3.0769230769231

To prove this, let's compute 40 divided by 3.0769230769231: $\frac{40}{3.0769230769231} = 13$

How does it work?

Asking what the value of x could be when 40 divided by x gives a result of 13, is equivalent to solving the following equation:

$\frac{40}{x} = 13$

Multiply both sides by x: $\frac{40 x}{x} = 13 x$
$\frac{40 x}{x}$ is equivalent to $\frac{x}{x} \times 40$ , which simplifies to $1 \times 40$ (or just $40$ ).
Thus, the equation becomes: $40 = 13 x$
To find x, divide both sides by 13: $\frac{40}{13} = \frac{13 x}{13}$
Which gives, after simplification: $3.0769230769231 = x$ (or $x = 3.0769230769231$ )

So, if the dividend is 40 and the quotient is 13, the divisor is 3.0769230769231.