What is x when 30 divided by x equals 10?

To find the answer, just divide the dividend by the quotient: 30 ÷ 10 = 3

To prove this, let's compute 30 divided by 3: $\frac{30}{3} = 10$

How does it work?

Asking what the value of x could be when 30 divided by x gives a result of 10, is equivalent to solving the following equation:

$\frac{30}{x} = 10$

Multiply both sides by x: $\frac{30 x}{x} = 10 x$
$\frac{30 x}{x}$ is equivalent to $\frac{x}{x} \times 30$ , which simplifies to $1 \times 30$ (or just $30$ ).
Thus, the equation becomes: $30 = 10 x$
To find x, divide both sides by 10: $\frac{30}{10} = \frac{10 x}{10}$
Which gives, after simplification: $3 = x$ (or $x = 3$ )

So, if the dividend is 30 and the quotient is 10, the divisor is 3.