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3 years ago

15

OK I need help the answer is c but I didn't understand the teacher explanation pls help me

1 answer:

serg [7]3 years ago

7 0

9 - 6 + 4 - 8/3 ..,
geometric series a(n) = a1r^(n-1)

r = a(n+1)/a(n)
-6/9 = -2/3
4/-6 = -2/3
-8/3/4 = -2/3
so r = -2/3 and a1 = 9

Sn = a1(1-r^n)/(1-r) = 9(1-(-2/3)^n)/(1-(-2/3))
n is infinite Sn = 9/(5/3) = 27/5

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Answer:

After 25 years the population will be:

Australia: 22271200
China: 1580220878
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Zaire: 112794819

Step-by-step explanation:

Growth rate problem that has a growth rate proportional to the population size can be solved using the equation:

P(t) = P₀eʳᵗ

t is your unit of time. It could be days, or hours, or minutes. It changes depending on each problem. In this problem, t is measured in years because you're jumping from 2000 to 2025. Years just makes the most sense to measure that leap in time.

P(t) is the population at time t. An example in this problem could be P(20) would be the population 20 years after the initial count. or maybe P(12) would be the population 12 years after the initial count. or P(0) would be the initial count of the population.

P₀ is the initial population at P(0)
r is the growth rate.<u><em> Don't forget to convert the percentage to its decimal form</em></u>

Now that everything is set out, lets use the equation to solve for our answer.

P(t) = P₀eʳᵗ

<u>Australia:</u>

$P(t)=(19169000)e^{(0.006)t}$

after 25 years

$P(25)=(19169000)e^{(0.006)(25)}=22271200.6$

<u>China:</u>

$P(t) = (1261832000)e^{(.009)t}$

after 25 years:

$P(25)=(1261832000)e^{(.009)(25)}=1580220878$

<u>Mexico:</u>

$P(t) = (100350000)e^{(0.018)t}$

after 25 years:

$P(25)=(100350000)e^{(0.018)(25)}=157380127.8$

<u>Zaire:</u>

$P(t) = (51965000)e^{(0.031)t}$

after 25 years:

$P(25)=(51965000)e^{(0.031)(25)}=112794819.9$

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3 years ago

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yuradex [85]

Answer:

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3 years ago

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Step-by-step explanation:

Let x represent the number of burgers that you bought.

Let y represent the number of tacos that you bought.

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