The probability of the weather being nice the next day or not depends on whether the sky is red at night or not. The sailor can use probability to tell whether the weather will be nice the next day or not. If the sky is red that night , then the next day will bring nice weather, but if the sky is not red that night, the weather wont be good the next day. (Don’t know if this is right or not but I hope it helps (: )
