U-238 decays to lead-206 by means of a series of decays.
One nucleus of U-238 eventually decays into one nucleus of lead-206
Over time the ratio of lead-206 atoms to U-238 atoms increases. This can be used to age certain types of rock.
In a particular rock sample, the ratio
number of Pb-206 atoms/number of U-238 atoms = 1/2
Show that the ratio:
number of U-238 atoms left/number of U-238 atoms initially = 2/3
Assume that the sample initially contained only U-238 atoms and subsequently it contains only U-238 atoms and lead-206 atoms.
I have no idea how to go about this so any help is greatly appreciated!