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Makovka662 [10]
3 years ago
5

How many hours will it take a culture of bacteria to increase from 20 to 2000? Use k= 0.614

Mathematics
1 answer:
nikdorinn [45]3 years ago
5 0

Answer:

it will take about 7.5 hours to increase from 20 to 2000

Step-by-step explanation:

y(t) = a  e^kt

20 = a e^ kt1

2000 = a e^ kt2

divide these equations

2000/20 = a e^ kt2/ a e^ kt1

when dividing the exponents subtract

100 =a/a e^(kt2-kt1)

factor out the k

100 = e ^ k(t2-t1)

take the natural log on each side

ln(100) = ln (e^ k(t2-t1)

ln (100) = k(t2-t1)

divide by k

ln(100)/k = (t2-t1)

we know k=.614

ln(100)/.614 = t2-t1

7.500277 = t2-t1

it will take about 7.5 hours to increase from 20 to 2000

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The number of lines and triangles illustrates combination

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<h3>The number of lines that can be drawn</h3>

The given parameters are:

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The number of lines that can be drawn is then calculated  using the following combination formula

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Hence, 36 lines can be drawn to join the nine points

<h3>The number of triangles that can be drawn</h3>

The given parameters are:

Total points, n = 9

Total points on each triangle, r = 3

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Read more about combination at:

brainly.com/question/11732255

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2 years ago
How are percent error and percent change similar
mihalych1998 [28]
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3 years ago
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Answer:

the second one(20)

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scoundrel [369]

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