The $$\(\mathbf{4}\)$$ Cones is an elite cappella vocal group. To be accepted, a Cone has to be good at setting up chairs in the theatre and have a great voice. In fact, each Cone works at the same rate; together the four can set up every chair in the theatre in 56 min . At this rate, it would take $$\(\frac{9}{2}\)$$ min. for 7 Cones to set up every chair.

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