How long can a lobster live?

This lobster weighs 25 pounds.  How old is it?

Let's have fish for supper! Walking into the Chatham Pier Fish Market,  she was in awe.  There in the front case was the largest lobster she had ever seen!  "How much does that lobster weigh?"  "25 pounds."  "How old is it then?"  "Well, it takes a lobster about 5 years to grow to a pound and then another 5 years for every pound after that, so this lobster is about 100 years old," commented the fishwife behind the counter.    "Maybe someone will keep it for a pet," replied Marash Girl.