A bag contains 20 coloured balls . 8 are red , 6 are blue ,3 are green ,2 are white and 1 is brown. A ball is chosen at random from the bag . What is the probability that ball chosen is :
not brown

Answer

To find the probability that a ball chosen at random from the bag is not brown, we can follow these steps:

### Step 1: Determine the total number of balls in the bag.
The bag contains:
- 8 red balls
- 6 blue balls
- 3 green balls
- 2 white balls
- 1 brown ball

**Total number of balls = 8 + 6 + 3 + 2 + 1 = 20 balls.**

### Step 2: Determine the number of favorable outcomes.
Favorable outcomes in this case are the balls that are not brown. We can find this by adding the number of red, blue, green, and white balls:
- Red balls: 8
- Blue balls: 6
- Green balls: 3
- White balls: 2

**Total favorable outcomes (not brown) = 8 + 6 + 3 + 2 = 19 balls.**

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

\[ P(\text{not brown}) = \frac{\text{Number of favorable outcomes}}{\text{Total number of outcomes}} \]

Substituting the values we found:

\[ P(\text{not brown}) = \frac{19}{20} \]

### Final Answer:
The probability that the ball chosen is not brown is \( \frac{19}{20} \).

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