A bag conains 30 blue ribbons, 15 red ribbbons and 5 black ribbons. If a ribbon is drawn at random from the bag, then find the probability of getting a red ribbon.

Options

A. `3//10`
B. `5//12`
C. `15//25`
D. `2//11`

Answer

To find the probability of drawing a red ribbon from the bag, we can follow these steps:

### Step 1: Determine the total number of ribbons.
We have:
- Blue ribbons = 30
- Red ribbons = 15
- Black ribbons = 5

**Total number of ribbons = Blue + Red + Black**
\[ \text{Total} = 30 + 15 + 5 = 50 \]

### Step 2: Identify the number of favorable outcomes.
The number of favorable outcomes for drawing a red ribbon is the number of red ribbons, which is 15.

### Step 3: Calculate the probability.
The probability \( P \) of an event is given by the formula:
\[ P(\text{Red Ribbon}) = \frac{\text{Number of favorable outcomes}}{\text{Total number of outcomes}} \]
Substituting the values we found:
\[ P(\text{Red Ribbon}) = \frac{15}{50} \]

### Step 4: Simplify the fraction.
To simplify \( \frac{15}{50} \), we can divide both the numerator and the denominator by their greatest common divisor, which is 5:
\[ P(\text{Red Ribbon}) = \frac{15 \div 5}{50 \div 5} = \frac{3}{10} \]

### Final Answer:
The probability of drawing a red ribbon from the bag is \( \frac{3}{10} \).

---