Problems in mathematics

Problems

 * FORTY + TEN + TEN = SIXTY
 * http://lamonica.info/CAOSPuzzle/T.html


 * SEND + MORE = MONEY
 * Henry Dudeney, in Strand Magazine vol. 68 (July 1924), pp. 97 and 214.


 * Perhaps no puzzle of the whole collection caused more jollity or was found more entertaining than that produced by the Host of the "Tabard," who accompanied the party all the way. He called the pilgrims together and spoke as follows: "My merry masters all, now that it be my turn to give your brains a twist, I will show ye a little piece of craft that will try your wits to their full bent. And yet methinks it is but a simple matter when the doing of it is made clear. Here be a cask of fine London ale, and in my hands do I hold two measures—one of five pints, and the other of three pints. Pray show how it is possible for me to put a true pint into each of the measures." Of course, no other vessel or article is to be used, and no marking of the measures is allowed. It is a knotty little problem and a fascinating one. A good many persons to-day will find it by no means an easy task. Yet it can be done.
 * Henry Dudeney, The Centerbary Puzzles, 6.—The Host's Puzzle.