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teller
 one year ago
Can someone please help me ?
The halflife of a radioactive isotope is the time it takes for a quantity of the isotope to be reduced to half its initial mass. Starting with 165 grams of a radioactive isotope, how much will be left after 3 halflives?Use the calculator provided and round your answer to the nearest gram.
teller
 one year ago
Can someone please help me ? The halflife of a radioactive isotope is the time it takes for a quantity of the isotope to be reduced to half its initial mass. Starting with 165 grams of a radioactive isotope, how much will be left after 3 halflives?Use the calculator provided and round your answer to the nearest gram.

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anonymous
 one year ago
Best ResponseYou've already chosen the best response.0\[A=A_0\cdot \left( \frac{ 1 }{ 2 } \right)^k\]where \(A_0\) is the initial amount \(A\) is the amount remaining after k halflives and k is the number of halflives

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0no... A = 165*(1/2)^3

teller
 one year ago
Best ResponseYou've already chosen the best response.0but it has to be rounded to the nearest gram how do I do that? It can't be in fraction form.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0divide and see what you get... the problem says to use the calculator provided but any calculator will work... or you can use long division

teller
 one year ago
Best ResponseYou've already chosen the best response.0divide it by what do I divide 165 by 8?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0yes, that is another way to represent 165/8

teller
 one year ago
Best ResponseYou've already chosen the best response.0I got 20.625 is that right?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0does that make sense to you? what is 20 * 8?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0so let's rewrite: \[\frac{ 20\cdot 8 }{ 8}+\frac{ 5 }{ 8 }=\frac{ 160 }{ 8 }+\frac{ 5 }{ 8 }=\frac{ 165 }{8}\]and 5/8 is less than 1 but more than 1/2 = .5, correct?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0so final answer, rounded to the nearest gram?

teller
 one year ago
Best ResponseYou've already chosen the best response.0I'm confused at what I'm supposed to be rounding...

teller
 one year ago
Best ResponseYou've already chosen the best response.0But how do I do that I already did that and I gave you the answer but you never told me if it was right.

teller
 one year ago
Best ResponseYou've already chosen the best response.0I got that but how do I round that?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.020.625 is not rounded to the nearest gram... 20.625 grams is the exact answer but they want the answer rounded to the nearest gram. which is closer to 20.625... 20 or 21?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0no... to the nearest gram... no numbers after the decimal!!!

teller
 one year ago
Best ResponseYou've already chosen the best response.0Mind helping me with another one?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0i would but i'm heading out. going for a bike ride. good luck!
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