A bag contains 7 white balls ,9 green balls and 10 yellow balls . A ball is drawn at random from the bag . What is the probability that it will be
not yellow

Answer

To find the probability that a ball drawn at random from a bag containing different colored balls is not yellow, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the number of balls of each color:**
- White balls = 7
- Green balls = 9
- Yellow balls = 10

2. **Calculate the total number of balls in the bag:**
\[ \text{Total number of balls} = \text{White balls} + \text{Green balls} + \text{Yellow balls} \]
\[ = 7 + 9 + 10 = 26 \]

3. **Determine the number of favorable outcomes (not yellow):**
- The favorable outcomes are the white and green balls.
\[ \text{Favorable outcomes} = \text{White balls} + \text{Green balls} \]
\[ = 7 + 9 = 16 \]

4. **Calculate the probability of drawing a ball that is not yellow:**
\[ \text{Probability (not yellow)} = \frac{\text{Favorable outcomes}}{\text{Total outcomes}} \]
\[ = \frac{16}{26} \]

5. **Simplify the fraction:**
\[ \frac{16}{26} = \frac{8}{13} \quad (\text{by dividing both numerator and denominator by 2}) \]

### Final Answer:
The probability that the ball drawn is not yellow is \(\frac{8}{13}\).

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