If Lake View's population is 24000, then there are 24000-4000 = <<24000-4000=20000>>20000 people living in Seattle.
The total population of Seattle and Lake view is 20000+24000 = <<20000+24000=44000>>44000
Since the population in Boise is 3/5 times that of Seattle, there are 3/5*20000 = <<3/5*20000=12000>>12000 people living in Boise.
The three cities have a total population of 44000+12000=<<44000+12000=56000>>56000
#### 56000