\( \definecolor{colordef}{RGB}{249,49,84} \definecolor{colorprop}{RGB}{18,102,241} \)
Two digital billboards in a city display their special animations at different intervals: one every \(18\) minutes, the other every \(30\) minutes. If both animations start at the same time at \(9{:}00\) AM, after how many minutes will both billboards display their animations together again?
minutes