Camilla needs 12/3 = <<12/3=4>>4 batches of pizza dough.
4 batches of pizza would require 30 x 4 = <<4*30=120>>120 minutes
Camilla needs to bake the pizzas 12/2 = <<12/2=6>>6 times
6 times in the oven would take 30 x 6 =<<6*30=180>>180 minutes
Altogether, it would take 120 + 180 = <<120+180=300>>300 minutes to finish making 12 pizzas
300 minutes is 300/60 = <<300/60=5>>5 hours
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