Do we use conditional probability formula here

[Steven G]

I have to comment even if it's just for @Cubist.
You say 1-5 seconds. So what happens between 0 seconds and 1 second?

 

[Steven G]

Total unsafe would be 2 min 100 sec . so does it come to 93.88% possum will cross safely

100 seconds = 1 min 40 seconds. Totaling to 3 min 40 sec.

 

[BigBeachBanana]

So what happens between 0 seconds and 1 second?

The possum calculates the probability that it will survive.

 

[Cubist]

So what happens between 0 seconds and 1 second?

Perhaps the possum crosses the track backwards. Then, if the train arrives between 0s and 1s then she'll loose some tail length, but will survive