Final answer:
The sum of 2/5 and 3/10 is 7/10. This fraction is already in its simplest form, indicating a possible error in the provided answer choices.
Step-by-step explanation:
The student is asking to add 2/5 and 3/10 and leave the answer in reduced fraction form. To add these fractions, they first need a common denominator. Since 10 is a multiple of both 5 and 10, we can use 10 as the common denominator. We can thus keep 3/10 as it is, but we need to convert 2/5 to a fraction with a denominator of 10. To do this, we multiply both the numerator and the denominator of 2/5 by 2 to get 4/10.
Now that both fractions have the same denominator, we can add them: 4/10 + 3/10 which equals 7/10. This fraction is already in its simplest form, as 7 and 10 share no common factors other than 1. Therefore, the answer is 7/10, which is not one of the options provided in the original question, indicating there might have been an error in the options given.