There are 30*2 = <<30*2=60>>60 pieces of ham put on the pizza.
There are 30+12 = <<30+12=42>>42 pieces of sausage put on the pizza.
There are 30/6 = <<30/6=5>>5 pieces of pepperoni on each pizza slice.
There are 60/6 = <<60/6=10>>10 pieces of ham on each pizza slice.
There are 42/6 = <<42/6=7>>7 pieces of sausage on each pizza slice.
There are 5+10+7 = <<5+10+7=22>>22 pieces altogether on each slice of pizza.
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