1. Example 5 • Kamreen travels to school by bus 30% of the time, and the rest by bike. When she travels by bus, the probability of her being late is 0.2; when she travels by bike, this probability is 0.05. • Find the probability that she is late • Given she is late, what is the probability she used the bus? Solution

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3. Example 5 • Kamreen travels to school by bus 30% of the time, and the rest by bike. When she travels by bus, the probability of her being late is 0.2; when she travels by bike, this probability is 0.05. • Find the probability that she is late • Given she is late, what is the probability she used the bus? Solution (a) P( Late ) = P(Bus and Late ) or P( Bike and Late) (a) P( Late ) = 0.06 + 0.035 = 0.095 (b) P(Bus Late) =