This is the 2490th most frequent Korean word.
될까
"될까" means "Will it be?" or "Will it work?"
The word '될까' is replaced here with '뭘까', which also ponders over a possibility or solution in a curious manner.
이 문제의 답이 뭘까?
What could be the answer to this question?
Here, '될까' conveys pondering about a future hypothetical situation.
내일 날씨가 좋으면 어떨까?
What if the weather is nice tomorrow?
In this case, '틀까' adjusted to '될까요' is used to inquire gently or propose a hypothesis, implying a probability or question.