That line is causing an error because you don't have a $ in front of the variable. It should be: 
    $avg_additional =
        $avg_repeat_logins * $life_two / $life_one - 1;

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Notice that you can take out all of the parentheses in your statement.

In reply to Re: Need help in doing multiplication by btrott
in thread Need help in doing multiplication by fgcr

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