Per ticket depends on if you add other attractions with it (statue of liberty and empire state building). I got my tickets off of groupon for 36$ a ticket. But beware if you go that route you'll need to start your tour infront of the M&M factory in time square.
They have different prices, it depends on the package you want to include. For example, if you want to include the walk to the Statue of Liberty, or the bike ride through the central park.
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