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CEMC Gauss (Grade 8), 2010

Algebra Difficulty 2.0 Junior Find the answer Canada

To shovel all of the snow on his driveway, Kevin needs $12$ hours. Individually, Dave needs $8$ hours to shovel all of Kevin's snow, John needs $6$ hours to shovel all of Kevin's snow, and Allison needs $4$ hours to shovel all of Kevin's snow. If Kevin, Dave, John, and Allison all work together, how many minutes do they need to shovel all of Kevin's snow?

(A) $108$ (B) $120$ (C) $84$ (D) $96$ (E) $90$

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