which characters are you asking about?

I think by Mortal Kombat Deadly Alliance it takes place about ten years after teh first one, doesn't it?

Well Mythologies is supposed to be set two years before MK1 and ten years before MK4. And then another couple of years passes to Deadly Alliance.

Then Deadly Alliance and Deception are back-to-back and Armageddon isn't long after, a couple months at most.

So yeah, in Armageddon, they're all somewhere around ten years older than they were in MK1.

As far as exact ages for the characters who have have lived unnaturally long...
Quan Chi was born a demon and is "possibly as old as the Netherealm". Raiden and the other gods were created at the beginning of the realms too. So too old to count.
Shang Tsung is about 1000, give or take a few years. He's a human who's supposed to age faster than normal because of a curse, but stops his aging by stealing souls.
Goro is 2000. He was the MK champ for 500 of those years, and the prize for MK champs is that they don't age until they lose a tournament, but being that old is still probably natural for his race given that his father is still alive.
Kitana is, of course, somewhere around 10,000. Rain's about the same age. No idea if Jade and Tanya were alive when Kahn conquered Edenia, they could be younger. Either way, Edenians live so long because the gods mated with their ancestors.
Then there's the special case of Sub-Zero, who looks older than he really is. He's only in his 30's or 40's but the Dragon Medallion's power artificially aged him a bit so he's all gray haired and wrinkled.

Someone should do a timeline like they have for stuff like the Resident Evil games