The sausages take 5 minutes per sausage * 3 sausages = <<5*3=15>>15 minutes to cook.
The eggs take 4 minutes per egg * 6 eggs = <<4*6=24>>24 minutes to cook.
So in total, it takes 15 minutes for sausages + 24 minutes for eggs = <<15+24=39>>39 minutes to cook breakfast.
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