Your math is a little off here. I know it can be confusing.
40% of time option 1

40% of
remaining time option 2 means .4 x .6 = 24% of the time for option 2
that will leave 60% of the missed first option which is .6 x .6 = 36% of the time for option 3
An easy fix for what you want will be:
When user_4bet and random <= 20 raise 90% force
When user_4bet and random <= 50 raise 75% force
When user_4bet raise 85% force