DB<42> $num1 = 1990; $num2 = '19.90'

 DB<43> p $num1 == ("" . $num2*100)          # number->to_string->to_number
1
 DB<44>

##</code><code>##

 DB<41> say join "\n", grep { sprintf ("%03d",$_) != ("".($_/1000)*1000) } 0..99999

 DB<42> 

##</code><code>##

  DB<44> $num1 = '001990'; $num2 = '19.9'

  DB<45> p $num1 == ("" . $num2*100)                                          
1 
  DB<46> $num2 = '19.900'

  DB<47> p $num1 == ("" . $num2*100)
1

  DB<60> $num1 = '199e1'

  DB<61> p $num1 == ("" . $num2*100)
1

##</code><code>##

  DB<63> $num2*=100

  DB<64> p $num1 == "$num2"
1
  DB<65>