Code wrapped for clarity: 

perl -anle"++$h{$F[0]}[0];$h{$F[0]}[1]+=$F[1]}
{print qq[$_\t$h{$_}[0]\t],$h{$_}[1]/$h{$_}[0] for keys %h" munge.txt
4       3       42
1       3       195.333333333333
3       3       27.6666666666667
2       1       20

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In reply to Re: Data munging by BrowserUk
in thread Data munging by umasuresh

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