Dustin reads 1.25 pages a minute because 75 / 60 = <<75/60=1.25>>1.25
Dustin reads 50 pages in 40 minutes because 40 x 1.25 = <<40*1.25=50>>50
Sam reads .4 pages a minute because 24 / 60 = <<24/60=.4>>.4
Sam reads 16 pages in 40 minutes because 40 x .4 = <<40*.4=16>>16
Dustin reads 34 more pages than Sam because 50 - 16 = <<34=34>>34
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