NYS Lottery's Pick 10 game: You pick 10 integers between 1 and 80 (including 1 and 80). The state picks 20 numbers. If all 10 of your numbers are among the state's 20 numbers you win $500,000. (Note that the state won't give $500,000 to each winner if too many people get 10 numbers among the 20 but we will assume that you always get the $500,000 if you match the numbers.) On the webpage you will find the following information:
Winning Numbers Matched
|
Prize
|
Chances of Winning
|
10
|
$500,000*
|
1 in: 8,911,711
|
9
|
$6,000
|
1 in: 163,381
|
8
|
$300
|
1 in: 7,384
|
7
|
$40
|
1 in: 621
|
6
|
$10
|
1 in: 87
|
0
|
$4
|
1 in: 22
|
a) Show how you get the probabilities of winning all of the above amounts.
b) Find the expected winnings.
c) Find the expected gain after paying $1 to play.
d) Why do you think that you win something if you match 0 numbers, rather than say winning something if you match 5 numbers?