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Schach [20]
4 years ago
15

The amount of a sample remaining after t days is given by the equation P(t)=A(1/2)^(t/h), where A is the initial amount of the s

ample and h is the half-life, in days, of the substance. A sample contains 18% of its original amount of Radon-222. The half-life of Radon-222 is about 3.8 days. Which is the best estimate for the age of the sample?
Mathematics
2 answers:
s344n2d4d5 [400]4 years ago
5 0
The equation is:
P ( t ) = A * (1/2 )^(t/h)
If a sample contains 18% of the original amount of Radon - 222 and h = 3.8:
0.18 * A = A * ( 0.5 )^(t/3.8)   / : A ( we will divide both sides of the equation by A )
0.18 = ( 0.5 )^(t/3.8)
t/3.8 = log _{1/2}0.18
t / 3.8 = 2.47 ≈ 2.5
t = 3.8 * 2.5 = 9.5
Answer:
The best estimate for the age of the sample is 9.5 days.

S_A_V [24]4 years ago
5 0

Answer:

c. 9.4 days

Step-by-step explanation:

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Answer:

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Step-by-step explanation:

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4 years ago
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mrs_skeptik [129]

<u>Complete question:</u>

Refer the attached diagram

<u>Answer:</u>

In reference to the attached figure, (-∞, 2) is the value where (f-g) (x) negative.

<u>Step-by-step explanation:</u>

From the attached figure, it shows that given data:

f (x) = x – 3

g (x) = - 0.5 x

To Find: At what interval the value of (f-g) (x) negative

So, first we need to calculate the (f-g) (x)

(f – g ) (x) = f (x) – g (x) = x-3 - (- 0.5 x)

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⇒ 1.5 x – 3 < 0

⇒ 1.5 x < 3

⇒ x

⇒ x < 2

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7 0
3 years ago
1<br> Select all of the true statements about the two triangles shown below.
Gekata [30.6K]

Answer:

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Step-by-step explanation:

Hope it helps you in your learning process.

4 0
3 years ago
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Norma-Jean [14]

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Step-by-step explanation:

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Hope this helps.

8 0
3 years ago
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