So we have 30 times some number is equal to 100. You could say 30 × ? = 100, or in a more math-y way, [tex]30x=100[/tex], where x is the number we're trying to find (not to be confused with the times sign). To find x, we need to isolate it (get it alone).
For [tex]30x=100[/tex], we divide both sides of the equation by 30.
[tex] \dfrac{30x}{30}= \dfrac{100}{30} [/tex]
On the left side, the 30's cancel, so we get [tex]x = \frac{100}{30} [/tex], but we're not done. We need to simplify this fraction.
We can rewrite the fraction with common factors in mind, like
[tex] \dfrac{(10)(10)}{(3)(10)}= \dfrac{10}{3} [/tex].
With more practice, this will seem more automatic to you.
This fraction is now in simplest form, so our final answer is
[tex]x = \dfrac{10}{3} [/tex]
