Dumb rules question from someone dumb

[OooMatron]

Hi...

I wonder if someone can help me with a question about the PF bestiary.

I get how the dragon advancement tables work on page 91, but looking at the sample dragon stats, I can't for the life of me work out how the "adds" to the hit dice are calculated.

For example, a young black dragon's hit dice are listed as 8d12+24, whereas an adult black dragon's hit dice are listed as 14d12+70.

I can't see where the +24 and +70 is coming from on the tables, and there doesn't seem to be any sensible mathematical link between these figures (not that maths was ever my strong point).

Does anyone know how these are worked out when advancing a dragon using the tables on page 91?

Thanks

[Whale_Cancer]

Increased constitution scores. Possibly also feats (toughness)

[Bearded Ben]

It's the extra hit points from the dragon's Constitution modifier times the number of hit dice. Both change as the dragon ages, so I see how that might not be clear at first.

[Gauss]

The +24 and +70 are coming from bonuses such as constitution bonuses.

The young black dragon has a con of 17 which is a +3 bonus. +3*8HD = +24
The Adult Black Dragon has a con of 21 which is a +5 bonus. +5*14HD = +70

Edit: ninja'd!

- Gauss

[P.H. Dungeon]

The 24 is assuming a 16 or 17 Con, which is adding 3 hp per hit dice (i.e., 8 x 3 = 24)

The older dragon's Con has advanced to 20-21 so it gets 5 hp per hit dice, 14 x 5 = 70

[OooMatron]

Thank you everyone! That was driving me crazy!

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