A tiger shark has 180 teeth.  A hammerhead shark has 1/6 the number of teeth that a tiger shark has.  A great white shark has double the sum of teeth of a tiger shark and a hammerhead shark. How many teeth does a great white shark have?
Hammerhead shark:180/6=<<180/6=30>>30
Great White:2(180+30)=420 teeth
#### 420