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2 years ago

Solve for n. 7+2n = 11

Mathematics

2 answers:

TiliK225 [7]2 years ago

7 0

7+2n=11
-7 -7
2n=4
/2 /2
N=2

Musya8 [376]2 years ago

5 0

Answer:

Step-by-step explanation:

7+2n = 11

2n = 11-7

2n = 4

n = 4/2

therefore n = 2

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Problem 10: A tank initially contains a solution of 10 pounds of salt in 60 gallons of water. Water with 1/2 pound of salt per g

AysviL [449]

Answer:

The quantity of salt at time t is $m_{salt} = (60)\cdot (30 - 29.833\cdot e^{-\frac{t}{10} })$ , where t is measured in minutes.

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This equation is solved as follows:

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$c = 30 + C\cdot e^{-\frac{t}{10} }$

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Now, the integration constant is:

$0.167 = 30 + C$

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The solution of the differential equation is:

$c(t) = 30 - 29.833\cdot e^{-\frac{t}{10} }$

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