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3 years ago

Please help me with this MATH question.

Mathematics

1 answer:

andrey2020 [161]3 years ago

3 0

Answer:

y=4

Step-by-step explanation:

84=30y-9y, first you collect like terms.

84=21y, swap the sides

21y=84, devide both sides and you get y =4

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Step-by-step explanation:

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Answer:

A) 63.36 years.

B) 100.42 years.

Step-by-step explanation:

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A) Since we know that population increases exponentially, therefore we will use our given information to form an exponential model for population increase and then we will solve for the time by which our population will be double.

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Now let us solve for t using logarithm.

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Therefore, it will take 63.36 years the population to be double.

B) Now we will find the number of years it will take the population to be triple of its size.

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$ln(3) =ln (1.011)^{t}$

$ln(3) =t \cdot ln(1.011)$

$1.0986122886681097 =t \cdot 0.0109399400383344$

$t=\frac{1.0986122886681097}{0.0109399400383344}$

$t=100.4221490079915311298\approx 100.42$

Therefore, it will take 100.42 years the population to triple of its size.

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