An urn contains one black ball and one green ball. A second urn contains one white and one green ball. One ball is drawn at random from each urn.
What is the probability that both balls are of same colour?

Options

A. `1//2`
B. `1//3`
C. `1//4`
D. `2//3`

Answer

To solve the problem, we need to determine the probability that both balls drawn from the two urns are of the same color.

### Step-by-Step Solution:

1. **Identify the contents of each urn:**
- Urn 1 contains: 1 Black Ball (B) and 1 Green Ball (G).
- Urn 2 contains: 1 White Ball (W) and 1 Green Ball (G).

2. **List all possible outcomes when drawing one ball from each urn:**
- From Urn 1, we can draw either:
- B (Black)
- G (Green)
- From Urn 2, we can draw either:
- W (White)
- G (Green)

The possible combinations of draws from both urns are:
- (B, W)
- (B, G)
- (G, W)
- (G, G)

3. **Determine which outcomes have balls of the same color:**
- The pairs of balls drawn that are of the same color are:
- (G, G) - both are Green.

4. **Count the total outcomes and favorable outcomes:**
- Total outcomes = 4 (as listed above).
- Favorable outcomes = 1 (only (G, G)).

5. **Calculate the probability:**
\[ \text{Probability} = \frac{\text{Number of favorable outcomes}}{\text{Total outcomes}} = \frac{1}{4} \]

### Final Answer:
The probability that both balls drawn are of the same color is \( \frac{1}{4} \).

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