Suppose the original price is 1.

A: The increased price is (1+a) * (1+b) =1+a+b+ab.

B: The increased price is [1+(a+b)/2]? = 1+(a+b)？ /4+a+b

∵ (a+b)？ /4-ab=[(a+b)？ -4ab]/4=(a-b)？ /4 & gt； 0(∵a≠b)

∴ (a+b)？ /4 & gt； abdominal muscle

That is, B has raised the price.