# Probability question?

In a 30 card deck
I have 4 A cards and I have 8 B cards
I draw 7 cards
Event A:
The cumulative probability of getting at least 1 A card is 0.68 according to http://stattrek.com/online-calculator/hypergeometric.aspx
Event B:
The culmulative probability of getting at least 2 B cards is 0.62
The...
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In a 30 card deck

I have 4 A cards and I have 8 B cards

I draw 7 cards

Event A:

The cumulative probability of getting at least 1 A card is 0.68 according to http://stattrek.com/online-calculator/hypergeometric.aspx

Event B:

The culmulative probability of getting at least 2 B cards is 0.62

The probability of event A and event B happening at the once is 0.62 x 0.68 = 0.42

Is the probability of event A and or event B

(0.62 + 0.68)/2 = 0.65?

Or should it be higher than 0.68%?

Should it be 0.62 + 0.68 - 0.42 = 0.88?

Thank you!

I have 4 A cards and I have 8 B cards

I draw 7 cards

Event A:

The cumulative probability of getting at least 1 A card is 0.68 according to http://stattrek.com/online-calculator/hypergeometric.aspx

Event B:

The culmulative probability of getting at least 2 B cards is 0.62

The probability of event A and event B happening at the once is 0.62 x 0.68 = 0.42

Is the probability of event A and or event B

(0.62 + 0.68)/2 = 0.65?

Or should it be higher than 0.68%?

Should it be 0.62 + 0.68 - 0.42 = 0.88?

Thank you!

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