6000 + 1 years
Lololololol
There's nothing in scripture that says the earth is 6000 years old. The reference to the 7 days that God created the earth are not literal 24hr periods as some seem to think, which is where the notion that the earth is 6000 years old comes from. It's simply not true.
The "days" represent creative periods. The duration and time they took to complete are undefined.
So, we don't really know exactly, but scientists calculations of 4+ billion are generally accepted by LDS as a decently accurate.
LDS embrace science more than you'd think.
Nowhere is the actual age of the earth or the universe mentioned in the bible, however you could still hold to a literal 6 day creation and still be an Old Earther as they're called. I'm sure you know that but I'm just saying. You can believe in a literal Genesis creation account and still not believe the universe was 6k years old. I've never actually met ANYONE who thought the universe was 6k years old. Never.