Fixing arithmetics.
Fixing arithmetics.

And some reflow. Closes #2204, which is absolutely correct. Thanks!

tbrowder/doc,stmuk/doc,stmuk/doc,jonathanstowe/doc,dmaestro/doc,MasterDuke17/doc,jonathanstowe/doc,perl6/doc,jonathanstowe/doc,jonathanstowe/doc,perl6/doc,perl6/doc,dmaestro/doc,MasterDuke17/doc,MasterDuke17/doc,stmuk/doc,MasterDuke17/doc,stmuk/doc,perl6/doc,perl6/doc,dmaestro/doc,dmaestro/doc,tbrowder/doc,tbrowder/doc,stmuk/doc,jonathanstowe/doc,dmaestro/doc,tbrowder/doc