(adsbygoogle = window.adsbygoogle || []).push({}); A sample of tritium 3 decayed to 94.5% of its original amount after a year.

(a) What is the half-life of tritium-3?

(b) How long would it take the sample to decay to 20% of its original

amount?

The only equations given in my book are dm/dt = km and m(t) = m(0)e^kt but the mass is not given in the problem. Is there another equation I should be using or am I just not seeing what exactly I should be using from the problem?

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# Homework Help: Radioactive decay and finding half life

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