INNUMERACY: MATHEMATICAL ILLITERACY AND ITS CONSEQUENCES by John Allen Paulos, New York: Hill & Wang. 135 pp. $16.95

WHY is it fashionable, even chic, to flaunt an ignorance of mathematics? Why is the ability to calculate disprized? What traps does the ``educated'' person who is mathematically illiterate walk into unknowingly?

John Allen Paulos, professor of mathematics at Temple University, looks at these questions in his entertaining, thought-provoking book on ``innumeracy'' - the inability to quantify the risks, possibilities, costs, or payoffs of actions and events.

Paulos involves the reader in the fun of numeracy.

For example, a man shows you three cards, one black on both sides, one red on both sides, and one black-red. He offers you the following: Draw one of the cards from a hat, looking only at one face. Assume it's red. Now turn it over. You pay him $1 if the other side is also red, otherwise he pays you $1.

Is it a fair game? Read the book to find out.

You will learn how to have a fair coin toss with a biased coin and understand why the probability is 50 percent that 2 of 23 people have the same birthday, while it takes 253 to get a 50 percent probability that two have a particular birthday.

The personal cost to those, especially women, who yield to the notion that they can't understand math is well known. The social cost of widespread innumeracy is being paid daily. Low productivity is bad enough, but there's also counterproductivity in the belief and cash that go into medical quackery, parapsychology, astrology, and various forms of gambling that seem so seductive.

Paulos approaches his goal indirectly. ``Whence Innumeracy?'' the chapter that suggests means for correcting the problem, is the fourth of five. He says that too few teachers love math, find it fun, and have a passion to share it with their students. A root cause of this is an antimathematical bias affecting the selection and education of teachers. Too many teachers with this bias arrive in our elementary and high schools, where the attitudes toward math of all but a few are set. (Another factor is psychological, as expressed in the desire to pursue personalized mystical sources of truth, like the I Ching or Tarot cards. The result is an unnecessarily high proportion of innumerates among graduates.)

Paulos offers suggestions such as certifying retired engineers and scientists to teach math; employing roving math specialists, whose job is to make math fun at least some of the time; and, more radically, swapping teachers between elementary schools and colleges. His purpose is to get readers involved in the problem, to convince them of the need to act.

The most important thing, he says, is to get students to connect mathematical manipulative skills with real world problems. ``Students should do numerous problems, some practical, some fanciful.''

You might expect a book about mathematics to be loaded with formulas and abstract reasoning. Paulos avoids this, presenting his concepts entirely in words. Such hitherto abstruse topics as conditional probability, or permutations and combinations, are treated in a brief, entertaining, and comprehensible way without use of a single equation.

Should you read ``Innumeracy'' if you enjoy reading math problems and reasoning them out? Yes, it's fun.

Should you read it if you think you hate math and are turned off by math problems? Yes, you may even get turned on.