>perl -e "print 10.5 + 15.5 + 25.5"
51.5 (Unrounded)
>perl -e "print 11 + 16 + 26"
53 (Conventional, delta = 1.5)
>perl -e "print 10 + 16 + 26"
52 (Banker's, delta = 0.5)