question

algo mas delgado que una serpiente

answer
Unas papas fritas son mas que una serpiente

is this correct

Si'

Something more slender than a snake? I would say that your answer "some French fries" is a good one, but you left out a word, delgadas (since you chose a plural answer).

I would write is as:
Algunas papas fritas son mas delgadas que una serpiente

Trust drwls here but don't forget más with accent!

Sra

No, that is not correct. The answer to your question would be "algo más delgado que una serpiente" translates to "something thinner than a snake." If you are looking for an object thinner than a snake, a few examples could be a toothpick, a strand of hair, or a needle. These objects are much thinner than a snake. It's important to understand the context of the question in order to provide an accurate answer.