Rounding float in Ruby -

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i'm having problems rounding. have float, want round hundredth of decimal. however, can use .round turns int, meaning 2.34.round # => 2. there simple effect way 2.3465 # => 2.35

when displaying, can use (for example)

>> '%.2f' % 2.3465 => "2.35"

if want store rounded, can use 

>> (2.3465*100).round / 100.0 => 2.35

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