Half-Life Problem: Finding Time for Amount Reduction

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Homework Statement



A radioactive material has a half life of 1550 years. Find the time during which a given amount of this material is reduced to one forth.


I am really not sure how to do this since we have not covered it in class yet. But, a formula that I have found involves find the k value (whatever that is) of a 1550 half life.

k=ln2/1550 = 6.65

Any guidance please?
 
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Are you familiar with the concept of half life?
 
Not really. I read that the half life is the time it takes for a material or anything to decay, for example, to half. And two half lives it decays to 25%.

This makes me think that the answer to my problem is simply 1550 times 2 but it seems is should be more to it.
 
Your knowledge of half-life suffices for the purposes of the problem and your solution 2(1550) should be correct.
 
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