The cost of 3 pens is Rs. 30, then the cost of 2 pens is Rs. 20.

Answer

To determine whether the statement "The cost of 2 pens is Rs. 20" is true or false, we can follow these steps:

### Step-by-Step Solution:

1. **Find the cost of 1 pen:**
- The cost of 3 pens is Rs. 30.
- To find the cost of 1 pen, we divide the total cost by the number of pens:
\[ \text{Cost of 1 pen} = \frac{30}{3} = 10 \text{ Rs.} \]

2. **Calculate the cost of 2 pens:**
- Since we know the cost of 1 pen is Rs. 10, we can find the cost of 2 pens by multiplying the cost of 1 pen by 2:
\[ \text{Cost of 2 pens} = 10 \times 2 = 20 \text{ Rs.} \]

3. **Verify the statement:**
- The statement claims that the cost of 2 pens is Rs. 20. Since we calculated the cost of 2 pens to be Rs. 20, the statement is confirmed to be true.

### Conclusion:
The statement "The cost of 2 pens is Rs. 20" is **true**.