Jake has to descend 30 steps on 9 floors for a total of 9*30 = <<30*9=270>>270 steps
He descends 3 steps every second so he will descend 270 steps in 270/3 = <<270/3=90>>90 seconds.
Austin will get down after only a minute (60 seconds) so Jake will get down 90-60 = <<90-60=30>>30 seconds later.
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