### Home > MC1 > Chapter 5 > Lesson 5.2.4 > Problem5-77

5-77.

The probability of getting a white marble from a bag is $\frac { 1 } { 5 }$. If there are four white marbles in the bag, what is the total number of marbles in the bag?

$\text{Set up equivalent fractions. } \frac{1}{5} = \frac{4}{?}$

$\text{Solve for the missing denominator. }\frac{1}{5} = \frac{4}{20} \text{ since 20 is four times 5.}$

$20$ marbles