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desikool
Jun 17, 2010, 05:18 PM
1. In a regular deck of 52 cards, find the probability of drawing any 9 and any 10 without replacing the first card you drew?
2. Suppose you play the three digit number 917 in your state's lottery. What is the probability you will win? (You must "hit" the number in exact order)

Clough
Jun 17, 2010, 11:20 PM
Hi, desikool!

I'm curious as to why you're asking the questions. Would you mind sharing about that, please?

Thanks!

Unknown008
Jun 18, 2010, 11:21 AM
1.

How many different ways can you get a 9 and a 10 together?
You can get the first one as a 9 and the second one as a ten, or the first one as a ten and the second one as a 9.

This is given by P(a\ 9\ and\ a\ 10) = P(9,10) + P(10,9)

So, find the probability that you get a nine first. Since there are 4 9's, that probability is 4/52. Then, the probability of drawing a 10. Since there are 4 10's, the probability is 4/51 (51 because now, there is one card less).

Do the same for P(10, 9) and add then up.

2. How many different numbers are there? There are 1000 numbers, including 000. So, if you play one number of all of those, what probability do you get? That should be easy now.

Post your answers! :)