To expand on what others have said, a computer can only exactly represent numbers with an integer powers of 2 in the denominator (1/2, 1/4, 1/8, etc.). Any other denominator will result in a representation that continues indefinitely. The representation is either truncated or rounded, but in any event it is inexact. For example, 0.1 (decimal) is represented as 0.0001100110010011001... in binary. Much of the time, the tiny error is insignificant. However, these errors accumulate when you use repeated calculations, and can eventually cause complete loss of precision.

In reply to Re: Problem with numbers.. by spiritway
in thread Problem with numbers.. by tamaguchi

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