human
It takes Matthew 3 minutes to dig a small hole for shrubs and 10 minutes to dig a large hole for trees. How many hours will it take him to dig 30 small holes and 15 large holes?
assistant
How many minutes will it take him to dig 30 small holes? ** It takes 3 minutes to dig a small hole and he needs to dig 30 small holes so it will take 3*30 = <<3*30=90>>90 minutes
How many minutes will it take him to dig 15 large holes? ** It takes 10 minutes to dig a large hole and he needs to dig 15 large holes so it will take him 15*10 = <<10*15=150>>150 minutes
How many minutes will it take him to dig 30 small holes and 15 large holes? ** It will take 90 minutes to dig the small holes and 150 minutes to dig the large holes for a total of 90+150 = <<90+150=240>>240 minutes
How many hours will it take him to dig 30 small holes and 15 large holes? ** There are 60 minutes in 1 hour and he needs to dig for 240 minutes so that's 240/60 = <<240/60=4>>4 hours
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