perl -e 'print  201/10 == 20.10000000000000000 ? "eq" : "ne"'
eq

perl -Mbigrat -e 'print  201/10 == 20.10000000000000000 ? "eq" : "ne"'
eq

perl -e 'print  201/10 == 20.10000000000000142 ? "eq" : "ne"'
eq

perl  -Mbigrat -e 'print  201/10 == 20.10000000000000142 ? "eq" : "ne"'
ne