The problem is that you’re currently calling ceil on 30.to_f. Here’s how Ruby evaluates it:
(67)/(30.to_f.ceil)
# .ceil turns the float into an integer again
(67)/(30.0.ceil)
# and now it's just an integer division, which will be 2
67/30 # = 2
To solve this, you can just add parenthesis:
puts (67/30.to_f).ceil # = 3