Fixed power scopes don't have a zoom range. Instead a fixed 6x scope only magnifies 6 times. In other words, when looking through the scope a target at 600 yards appears only 100 yards away.

A 3-9x variable scope can magnify the target 3x or 9x or anywhere in between, depending on where you turn the magnification ring.

“Montana seems to me to be what a small boy would think Texas is like from hearing Texans.”
John Steinbeck