Question

a bag contains 3 red marbles, 3 white marbles, and 5 blue marbles. only white marbles will be added to the bag. how many white marbles should be added to the bag to make the probability of pulling a white marble 50%? enter the answer in the box.

Explanation:

Step1: Define variables

Let \( x = \) number of white marbles added.

Step2: Set up probability equation

Total marbles after adding: \( 3 + 3 + 5 + x = 11 + x \). White marbles: \( 3 + x \). Probability = \( \frac{3+x}{11+x} = 0.5 \).

Step3: Solve for x

\( 3 + x = 0.5(11 + x) \) → \( 3 + x = 5.5 + 0.5x \) → \( 0.5x = 2.5 \) → \( x = 5 \).

Answer:

5