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 blue

Answer

To find the probability that a ball chosen from the bag is not blue, we will follow these steps:

### Step 1: Determine the total number of balls in the bag.
The total number of balls is given as:
- Red balls = 8
- Blue balls = 6
- Green balls = 3
- White balls = 2
- Brown balls = 1

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

### Step 2: Identify the number of favorable outcomes.
The favorable outcomes for choosing a ball that is not blue include all the other colors:
- Red balls = 8
- Green balls = 3
- White balls = 2
- Brown balls = 1

**Total favorable outcomes = 8 + 3 + 2 + 1 = 14**

### 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:
\[ \text{Probability of not blue} = \frac{14}{20} \]

### Step 4: Simplify the fraction.
To simplify \(\frac{14}{20}\), we can divide both the numerator and the denominator by their greatest common divisor (GCD), which is 2:
\[ \frac{14 \div 2}{20 \div 2} = \frac{7}{10} \]

### Final Answer:
The probability that the ball chosen is not blue is \(\frac{7}{10}\).

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