One card is dealt. Find the chance that its color is red or its rank is an even number.

Question

nurali · Answer

http://openstudy.com/study#/updates/516a729be4b015a79c114825

terenzreignz · Answer

Good catch, @Nurali I completely forgot about that :D

anonymous · Answer

Chance of an even number - 2,4,6,8,10 of 4 different colors
chance of a red colour - 13*2=26
so 2,4,6,8 of 2 red colours are eliminated as they are contained in red colour cards 
so the probability is 26+ 10/52 that is 36/52

perl · Answer

P( red or even card ) = P(red ) + P(even) - P( red & even) 
                              = 26/52 + 20/52 - 10/52

perl · Answer

this is the addition rule
P( A or B ) = P(A) + P(B) - P(A&B)