Compound events help help!!!
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P(Getting a diamond) = 13/52;
P(Getting a 7) = 4/52
P(Getting a diamond AND getting a 7) = 1/52
So,
P(Getting a diamond OR getting a 7) = P(Getting a diamond) +
P(Getting a 7) = 4/52 -
P(Getting a diamond AND getting a 7)
= (13 + 4 - 1) / 52
= 16 / 52 = 4/13