I got bored while studying for my math exam and decided to calculate the age difference between Bilbo and Thorin using the logic of human ages.
Okay, first of all, considering that Dwarves have a lifespan of 250-300 years and Hobbits have an average lifespan of 100 years and reach adulthood at 33, I've come up with this logic:
Thorin was 195 years old on this adventure (in the film), and according to a calculation by a Quora user, Thorin human age is 55. Let's keep that in mind.
To find Bilbo's age during his adventure, we go to The Lord of the Rings movie, where he was 111 years old, and the film takes place 60 years after the adventure in The Hobbit. 111 - 60 = 51, so he was 51 hobbit age during his adventure with Thorin.
After determining Bilbo's Hobbit age, we move on to determining his human age, and here's the logic I used:
Hobbits age of majority is 25, which is equal to our age of 18. Therefore, we need to find out how much time has passed since he reached the age of majority, compared to his age in the adventure. 51 - 25 = 26, so 26 years have passed since he became an adult. In this case, we need to add 26 to our age of majority: 18 + 26 = 44. So, in human years, Bilbo is 44 years old.
And finally, we come to the age difference between them. For this, we do the following calculation: 55 - 44 = 11. So, using human age logic, there was a 11 year age difference between them.
(I failed the math exam, but oh well. It was definitely worth it.😌)
