# Probability/Outcome

A complete revision:

Match and Win Promotion

• A pre-selected envelope will contain 3 items in it.
• Nine (9) items will be on the board for a person to select only 3 of the items that they think is in the pre-selected envelope.
• The Match and Win Promotion will be on a Friday and Saturday Night over a seven (7) week period for a total of 14 promotional nights.
• Each night drawings will be conducted at 6 pm, 7 pm, 8 pm, 9 pm, 10 pm and 11 pm for a total of 6 different chances to win.
• Using a combinations formula of C(n,r) there are 84 possible combinations of choosing 3 out of 9 items. (if I did that corretly)
• Based on the number of combinations, there would be 84 envelopes created with each possible outcome in each envelope.
• Only 6 envelopes will be selected to use each promotional night then no longer used again. So envelopes will change each night.
• What is the probability of getting 3, 2, or 1 correct or nothing (0)?
Notes: Only 6 possible combinations are selected out of 84 on the first night. Then the second night will only have 78 possible combinations left and so on and so forth until the final night.

Hopefully this is easier to understand. Maybe...
• Why there are 84 possible outcomes? Where 84 comes from?

• I don’t understand how the different days/different drawings come into play. Are you the only person participating in these drawings? When you say “ What is the probability of getting one match out of 3?” do you mean “ever?” In any of the 42 drawings? Or on a particular drawing? Or before someone else does? Or what? It’s pretty hard to follow what you mean.

• I apologize. I will edit it and see if I can explain it better. I extended the deadline.

• I completely revised it, so I hope it helps.

• .1. If multiple contestants are participating, how do we know some envelopes won't be repeated? 2.If there is only one contestant, notice there are 84 chances of winning (14 nights times 6 attempts per night), so eventually one of the envelopes has to be right. The question is not sufficiently clear.

• Once an envelope is used, it cannot be used again. The guest will be shown what is in the envelope to see if they won and then it is discarded. It will be different people chosen each night but a person can be selected more than once as long as it is a different night.

• So your question can be paraphrased as, "If a contestant plays, what is the probability that they get 1 item right or 2 or 3?

• Correct