At Least Once If probability of an event happening is p, then the probability that the event happens at least once in n trials is 1-(1-p)∧n.8 w( `9 f& q+ ?, G8 ]+ Y5 f
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To understand the equation follow these steps: 1.The probability of the event not happening is 1-p. 9 R9 Q1 T" I) `# m0 r: \ 2.The probability it won't happen n-times in a row is (1-p)∧n.9 ?; N5 D" g' {2 j' ` ~3 x3 q
3.Probability it will happen at least once is 1-(1-p)∧n.4 x" @' m( W4 u H3 e
Probability that a roll of a six-sided die land with face 1 is 1/6.Then the probability that 1 will turn up at least once in 3 tries:=1-(1-1/6)∧3=1-(5/6)∧3.9 Y& D3 g H5 h" ^/ L2 G1 T
Remember: 0 o) J3 B+ ^, u& `8 E+ p It is much harder to directly calculate the at-least-once probability.