ng "x". If the older ring is 31 years old, then the difference in age between the two rings is 31 - 10 = 21 years.
We know that the older ring will be twice as old as the newer ring when the difference in age between them is x.
So, we can set up an equation:
31 - 10 = x
31 - x = 10
Now we know that in x years, the older ring will be twice as old as the newer ring.
Therefore, in x years the older ring will be 31 years old and the newer ring will be 10+x years old.
x = 21 years
So, in 21 years the older ring will be twice as old as the newer ring.