A bag contains 5 red and 8 green marbles. One marble is drawn from the bag at random. Find the probability that the marble drawn is red.

Answer

To find the probability that the marble drawn from the bag is red, we can follow these steps:

### Step 1: Identify the total number of marbles in the bag.
The bag contains:
- 5 red marbles
- 8 green marbles

To find the total number of marbles, we add the number of red marbles and green marbles together.

**Total number of marbles = Number of red marbles + Number of green marbles**
Total number of marbles = 5 + 8 = 13

### Step 2: Identify the number of favorable outcomes.
The favorable outcomes in this case are the number of red marbles since we want to find the probability of drawing a red marble.

**Number of favorable outcomes (red marbles) = 5**

### Step 3: Calculate the probability.
The probability of an event is given by the formula:

\[ \text{Probability} = \frac{\text{Number of favorable outcomes}}{\text{Total number of outcomes}} \]

In this case, the probability of drawing a red marble is:

\[ \text{Probability of red marble} = \frac{5 \text{ (favorable outcomes)}}{13 \text{ (total outcomes)}} \]

### Step 4: Simplify the probability.
Thus, the probability of drawing a red marble is:

\[ \text{Probability of red marble} = \frac{5}{13} \]

### Final Answer:
The probability that the marble drawn is red is \( \frac{5}{13} \).

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