(2) According to the meaning of the question: x+x+2+x+8+x+ 10=200,

Solution: x=45,

These four numbers are 45, 47, 53 and 55 in turn.

A: These four numbers are 45, 47, 53 and 55 in turn.

(3) it does not exist.

∫4x+20 = 420，

Solution: x= 100,

It's even, it doesn't matter, so it doesn't exist.