1.

Three numbers are chosen from 1 to 20. Find the probability that theyare consecutive.A. `(186)/(190)`B. `(187)/(190)`C. `(188)/(190)`D. `(18)/(.^(20)C_(3))`

Answer» Correct Answer - B
(b) Since, the set of three consecutive numbers from 1 to 20 are 123, 234, 345,…..,18, 19, 20 i.e., 18.
`"P(numbers are consecutive)"=(18)/(.^(20)C_(3))=(18)/(1140)=(3)/(190)`
`"P(three numbers are not consecutive)"=1-(3)/(190)=(187)/(190)`


Discussion

No Comment Found

Related InterviewSolutions