Hello! i was just wondering if anyone could help me with this,(adsbygoogle = window.adsbygoogle || []).push({});

The rubidium isotope 87-Rb is a beta emitter with a half life of 4.9 x 10^10 yr that decays into 87-Sr. It is used to determine the age of rocks and fossils. Certain rocks contain a ratio of 87-Sr to 87Rb of 0.0100. Assuming there was no 87-Sr present when the rocks were formed, calculate the age of these fossils.

So far all i can think of doing is taking 1% of the half life as the answer but i'm very uncertain!

Thanks for any help with this :-)

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# Homework Help: Using the decay rate of rubidium isotope to determine age of fossils

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