If it takes five machines five minutes to make five widgets, how long would it take 100 machines to make 100 widgets?
Correct: B
If it takes 5 machines 5 minutes to make 5 widgets, then each machine is making 1 widget in 5 minutes. Therefore, if there were 100 machines, it would still take 5 minutes for each machine to make 1 widget, so it would take 5 minutes for 100 machines to make 100 widgets.