The question in the picture is very different from the question before the picture.
Half of 12 is ____ is a different question than 12 is ____ halves
When you say, "Halves of 12, 10, ..." it looks like you're asking the first version.
One of something is 2 halves. That is, the number of halves is exactly two times the number of "somethings." Hopefully, you can multiply each of these numbers by 2.
