What is x when 30 divided by x equals 7?

To find the answer, just divide the dividend by the quotient: 30 ÷ 7 = 4.2857142857143

To prove this, let's compute 30 divided by 4.2857142857143: $\frac{30}{4.2857142857143} = 7$

How does it work?

Asking what the value of x could be when 30 divided by x gives a result of 7, is equivalent to solving the following equation:

$\frac{30}{x} = 7$

Multiply both sides by x: $\frac{30 x}{x} = 7 x$
$\frac{30 x}{x}$ is equivalent to $\frac{x}{x} \times 30$ , which simplifies to $1 \times 30$ (or just $30$ ).
Thus, the equation becomes: $30 = 7 x$
To find x, divide both sides by 7: $\frac{30}{7} = \frac{7 x}{7}$
Which gives, after simplification: $4.2857142857143 = x$ (or $x = 4.2857142857143$ )

So, if the dividend is 30 and the quotient is 7, the divisor is 4.2857142857143.