Math Tricks, Puzzles and Games

Rating:
Summary: Makes math fun
Review: Great book for making math fun and approachable...wish there more like it. I actually enjoyed and looked forward to helping my kid with math.

Rating:
Summary: 7 Year Old Finds Math Error In Math Tricks Book
Review: My 7 year old son found a serious math error in this book by Professor Numbers, aka, Ray Blum. On page 69, under "Mathematical Oddity", the author purports that the two columns of numbers have the same sum. The nine numbers in the left hand column of numbers are each greater than their counterpart in the right hand column. It goes without saying that the left hand column adds up to a higher number than the right. So much for basic math logic.

As an earlier review stated, this book basically recycles old math tricks. Not that this is a punishable offense, but the book fails to explain WHY the tricks work.

Rating:
Summary: Classic problems just right for fourth graders
Review: My fourth grade son recently purchased this book and he has been enjoying it ever since. He really likes the problems that appear to be magical, but are in fact simple applications of numbers. None of the problems are original, most would be considered classics, and some have been around for centuries. However, that does not detract from their quality, as they require a great deal of thought, some of it of the sideways variety. Like most good puzzles, successfully arriving at the solution sometimes requires that the obvious possibility be rejected in favor of a different approach.
A previous reviewer mentions that there is an error on page 69. That person is mistaken. The problem is correct as stated, the reviewer is simply not understanding that the numbers are not to be altered from their current alignment, which would mean the numbers that are left aligned are to be considered to have trailing zeros.
I enjoyed the book and my children are finding the problems to be challenging and educational. In no way do I regret allowing my son to purchase it.