Jerry mows 8 acres x ¾ = 6 acres with a riding mower.
It will take him 6 acres / 2 each hour = <<6/2=3>>3 hours.
Jerry mows 8 acres – 6 acres mowed with a riding mower = <<8-6=2>>2 acres with a push mower.
It will take him 2 acres x 1 hour = <<2*1=2>>2 hours.
It takes Jerry a total of 3 hours on the riding mower + 2 hours on the push mower = <<3+2=5>>5 hours.
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