Mathematical Brain-Teasers

Tantalizing teasers including coin and change problems, relative ages, time and distance, and 40 alphametics—innovative letter substitutions. Solutions.

Summary: 150 Challenging Brain-Teasers for the Math Puzzle Fanatic

Here you will find 150 tantalizing brain-teasers devised by one of the great contemporary inventors of mathematical puzzles. Over 100 problems are in cleverly worded story forms; coin and change problems, relative ages, time and distance problems. Many of these solutions could come up in everyday life. There are also a number of fine "alphametics", innovative letter substitutions you will find specially attractive. 

Here an example of the kind of mathematical teasers you will find in this book (#35. A matter of ifs): 

"If Sam had driven for twenty minutes less than the time he would have driven if he had driven twenty miles less than he did drive but at two-thirds the speed at which he drove, he would have driven ten miles less than he did. 
If he had driven twenty minutes longer than the time he would have driven if he had driven ten miles less than he did drive but at three-quarters the speed at which he drove, he would have driven twenty miles further. 
No more "ifs". But how far did Sam drive?" 

Try this mathematical brain-teaser, and if you like this one, you will definitively love this book.