The probablility that a companys work force has no accidents

The probablility that a company\'s work force has no accidents in a given month is 0.7. The number of accidents from month to month are independent. What is the probability that the third month in a year is the first month that at least one accident occurs?

Solution

P( at least one accidents) = 1 -P(x=0)

P( at least one accidents ) = 1 - [0.7*0.7*0.7]

P( at least one accidents ) = 0.657