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In a binomial distribution `B(n , p=1/4)`, if the probability of at least one success isgreater than or equal to `9/(10)`, then n isgreater than(1) `1/((log)_(10)^4-(log)_(10)^3)`(2) `1/((log)_(10)^4+(log)_(10)^3)`(3) `9/((log)_(10)^4-(log)_(10)^3)`(4) `4/((log)_(10)^4-(log)_(10)^3)` |
Answer» `0,1,2,3,4,..... , n` `P= 1- `all fail `S(P) = 1/4` `S(F) = 1 - S(P)` `= 1-1/4` `=3/4` `P= 1- (3/4)^n >= 9/10` `-9/10 >= (3/4)^n` `1/10 >= (3/4)^n` `-1 >= n log_10 3/4` `n <= -1/(log_10 3/4)` `<= -1/(log_10 3 - log_10 4) ` `n >= 1/(log_10 4 - log_10 3) ` Answer |
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