These numbers can only be added and subtracted at will, and cannot be changed, which is equal to 45.

What needs to be subtracted is half of 66-45 =2 1, that is, 10.5.

There is no such number as 0.5 in 1, 2, 3, 4, 5, 6, 7, 8, 9, 10,1,so this topic is wrong.