Math Is Fun Forum

AndrewP

Guest

Stats Question

I have this question:

The probability of winning the jackpot on the National Lottery is

which is 0.0000000715. How many tickets do I need to buy to have at least a 10% chance of winning the jackpot?

I am meant to either use the Binomial or the Poisson distribution for this, but I don't know how to approach this question.

Please could you help me?

Thank you in advance.

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Stats Question

Hi AndrewP;

You don't have to to use the binomial distribution.

1/ 0.0000000715 = 13 986 013.9
That means that there are a bit less than 14 million numbers, with only one grand prize winner.

You need to buy 1,398,602 tickets (all with different numbers).

If he is right about the structure: 13 986 014 different tickets and only one grand prize winner. Then it is hard to argue with his idea of buying 1 398 602 different tickets. This would give you slightly better than 10% chances. Provided as I said that this is the structure of the lottery.

Here is another entirely different answer that the boys over at NRICH came up with:

https://nrich.maths.org/discus/messages … 1197837835

Here is another which agrees with MornigF

http://grahamkendall.net/Math/Math%20Ne … mm-385.txt

Its about 2 /3 down the page.

Last edited by bobbym (2009-10-07 05:34:56)

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