Issue #9540 has been reported by Samu Voutilainen.

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Bug #9540: Number formatting with 4.225 fails
https://bugs.ruby-lang.org/issues/9540

* Author: Samu Voutilainen
* Status: Open
* Priority: Normal
* Assignee: 
* Category: 
* Target version: 
* ruby -v: ruby 2.1.0p0 (2013-12-25 revision 44422) [x86_64-linux]
* Backport: 1.9.3: UNKNOWN, 2.0.0: UNKNOWN, 2.1: UNKNOWN
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Hi,

When Im trying to floor number with line "%.2f" % 4.225, I get 4.22 as result, instead of 4.23. Rounding for example with0.025 correctly results to 0.03.

I tested this with both newest 2.0.0 patchset build and 2.1.0. 

Some example output done with irb:
<pre>
irb(main):016:0> "%.2f" % 4.2251
=> "4.23"
irb(main):017:0> "%.2f" % 4.2250
=> "4.22"
irb(main):018:0> "%.2f" % 4.225
=> "4.22"

irb(main):011:0> "%.2f" % 0.035
=> "0.04"
irb(main):012:0> "%.2f" % 0.025
=> "0.03"
</pre>



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