Final answer:
To add fractions with the same denominator, add the numerators and keep the same denominator.
Step-by-step explanation:
When adding fractions with the same denominator, you simply add the numerators and keep the same denominator. In the example 2/5 + 1/5, the denominators are the same, which is 5. So, you can add the numerators: 2 + 1 = 3. Therefore, the sum of 2/5 + 1/5 is 3/5.