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From: leonut <leonut.r2@gmail.com>
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Subject: (+ 5.1 0.1)
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First I used "emacs --no-init-file" to start my emacs-22.3, then I
typed (+ 5.1 0.1) in *scratch* buffer. However, when I evaluated this
expression, I got 5.199999999999999.
Can anyone tell me why did this happen?
I tried (+ 5.0 0.1) and (+ 5.2 0.1) and both gave the answers I had
expected.