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Oksanka [162]
3 years ago
5

After 3 days a sample of radon-222 has decayed to 58% of its original amount.(

Mathematics
1 answer:
iren2701 [21]3 years ago
3 0
Half-life = [elapsed time * log (2)] / [log (begng amt / endg amt)]
half-life =  (3 days * 0.30102999566) / log (1 / .58)
<span>half-life =  0.903089987 / log </span> (<span> <span> <span> 1.724137931)
</span></span></span>half-life =  <span>0.903089987 / 0.23657200643</span>
half-life =  <span> <span> <span> 3.8174 days

Source:
http://www.1728.org/halflife.htm

</span></span></span>
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Shalnov [3]

Answer:

V =113.04

Step-by-step explanation:

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Divide each side by 12.56

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3 years ago
Bruno claims that the solution to the linear equation −3(2x+6)+25=1 is x=1. He shows the steps below to justify his solution.
jonny [76]

Answer:

Bruno is correct x=1

Step-by-step explanation:

-3(2x+6)+25=1

-6x-18+25=1

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6 0
3 years ago
Help please please !!!!!!!
lyudmila [28]
In each case, you can use the second equation to create an expression for y that will substitute into the first equation. Then you can write the result in standard form and use any of several means to find the number of solutions.

System A
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System B
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Answer:

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Step-by-step explanation:

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2 years ago
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IgorLugansk [536]

Answer:

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Step-by-step explanation:

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3 years ago
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