Three reds

What is the probability that all three cards drawn from a set of seven cards — three of which are red — will be red?

Final Answer:

p =  1.129 %

Step-by-step explanation:

C3​(8)=(38​)=3!(8−3)!8!​=3⋅2⋅18⋅7⋅6​=56  C3​(32)=(332​)=3!(32−3)!32!​=3⋅2⋅132⋅31⋅30​=4960  p=100⋅ (332​)(38​)​=100⋅ 496056​=4960100⋅ 56​=49605600​=3135​≐1.129%   Verifying Solution:  p1​=100⋅ 32⋅ 31⋅ 308⋅ 7⋅ 6​=3135​≐1.129 %

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Showing 2 comments:
Math student
This question could be improved by including some basic info about carats.  I thought it was a unit of measure for gemstones, but apparently it's a card game of some kind?  Also, "all three reds will be red" sounds like a tautology.

Dr Math
Yes, we improved spelling. Not carats, but cards ;)





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