Hi,

IRB with utility_belt displays Rational numbers without the "/" sign:
daniel@daniel-desktop:~$ irb -r mathn
>> 4/5
=> 45
>> (4/5).class
=> Rational
>> (4/5).to_s
=> "4/5"
>> (4/5).inspect
=> "4/5"

Without utility_belt:
daniel@daniel-desktop:~$ irb -f -r mathn
irb(main):001:0> 4/5
=> 4/5
irb(main):002:0> (4/5).class
=> Rational
irb(main):003:0> (4/5).to_s
=> "4/5"
irb(main):004:0> (4/5).inspect
=> "4/5"