Do you really mean that with 30 days in stead of 1 day, you have 29% more chance? Or is it 30 times as much, which is 2900% more chance? In that case I wouldn't write the program yourself.
The best program to use depends on where the needed data - about visitors and (number of) visits - is stored. But if it's accessible in Excel, a lottery program is easy to write in a macro using the RAND or RANDBETWEEN function.
Hello friends,
I am in search of something which acts like a lottery but where is can configure the chance of someone winning more than others. Here is what is in my mind,
I own a small gaming zone in Nepal.So, i was hoping to draw 4 lucky winner every month among my customers for some giveaways. So, i want the customer who visit more to have more chance of winning than a customer who visits less. Something like if i visit everyday(30 days/month) and a guy visits 1 day. I have 29% more chance to win than the guy who visits only 1 day.

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