Two pipes are connected to the same tank. when working together., they can fill the tank in 10hrs. the larger pipe, working alone, can fill the tank in 15 hrs less time than the smaller one. how long would the smaller one take, working alone, to fill the tank

Aprobability experiment is conducted in which the sample space of the experiment is s={7,8,9,10,11,12,13,14,15,16,17,18}, event f={7,8,9,10,11,12}, and event g={11,12,13,14}. assume that each outcome is equally likely. list the outcomes in f or g. find p(f or g) by counting the number of outcomes in f or g. determine p(f or g) using the general addition rule.