secrets-of-mental-math-malestrom

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Foreword
whispering or making other sounds while you calculate? It
almost always makes math easier. The problem, though, is that
other people think you’re a little odd . . . not even (more math
humor). Well, in Secrets of Mental Math, Dr. Benjamin helps
you learn to use that “out-loud” feature of the way your brain
works to do math problems more easily, faster, and more accurately
(which is surprising), all while your brain is thinking
away—almost as if you’re thinking out loud.
You’ll learn to move through math problems the same way
we read in English, left to right. You’ll learn to handle big problems
fast with good guesses, actually great guesses, within a percent
or so. You will learn to do arithmetic fast; that way you can
spend your time thinking about what the numbers mean. Og
wondered, “Do we have enough fruit for each person sitting
around the fire? If not, there might be trouble.” Now you might
wonder, “Is there enough space on this computer to keep track
of my music files . . . or my bank account? If not, there might be
trouble.”
There’s more to Secrets than just figuring. You can learn to
take a day, month, and year, then compute what day of the week
it was or will be. It’s fantastic, almost magical, to be able to tell
someone what day of the week she or he was born. But, it’s
really something to be able to figure that the United States had
its first big Fourth of July on a Thursday in 1776. April 15,
1912, the day the Titanic sank, was a Monday. The first human
to walk on the moon set foot there on July 20, 1969, a Sunday.
You’ll probably never forget that the United States was attacked
by terrorists on September 11, 2001. With Secrets of Mental
Math, you’ll always be able to show it was a Tuesday.
There are relationships in Nature that numbers describe better
than any other way we know. There are simple numbers that
you can count on your hands: one, two, three, and on up. But