Ray's Arithmetical Key

Containing Solutions To The Questions In Ray'S Third Book, And To Some Of The Most Difficult Questions In The Second Book: Also An Appendix, Of Test Examples Fo... » 

Containing Solutions To The Questions In Ray'S Third Book, And To Some Of The Most Difficult Questions In The Second Book: Also An Appendix, Of Test Examples For The Slate Or Blackboard. By Joseph Ray ... «