Question

@Hoslos @Nurali @TylerD I dont even know how to do it. Population of a city. The population of a certain city was 112,000 in 1998, and the observed relative growth rate is 4% per year. (a) Find the function that models the population after t years. (b) find the projected population in the year 2004. (c) in what year will the population reach 200,000?

Answer 1

@Hoslos hey

Answer 2

@TylerD hey

Answer 3

@triciaal @abb0t @appleduardo know how to do it

Answer 4

@sammixboo @dan815 know how to do it

Answer 5

@uri please help me pplz

Answer 6

@ShelbyRenaebb @Algorithmic help me

Answer 7

@uri come back

Answer 8

@appleduardo the last part mostly

Answer 9

@triciaal can u help

Answer 10

its the same formula, dP/dt = kP, but in this case we know k which 4%, and we represent it with: dP/dt=0.04P

Answer 11

now you do the integration, and apply your limits and your done

Answer 12

i am reading the question

Answer 13

@sammixboo can u help

Answer 14

@appleduardo im not getting 2008

Answer 15

@ShelbyRenaebb i need help pplz

Answer 16

@triciaal for part c im not getting 2008

Answer 17

(a) Find the function that models the population after t years.
f(t) = 0.04t + 112000

Answer 18

Is this trig? Or what?

Answer 19

@ShelbyRenaebb pre-calculus

Answer 20

Yeah ive only took algebra 2 and geometry. Not there yet im sorry D: Do you go to connections?

Answer 21

i saw this on differential equations lol

Answer 22

(b) find the projected population in the year 2004.
start 1998 now 2004 how many years past? this is t
find f(t) with with value

Answer 23

@ShelbyRenaebb i can do this; but this problem threw me off. im n college

Answer 24

@triciaal is it 8 or 9 im not sure

Answer 25

You can use geometric progression formula. Nth:ar ^n-1, therefore, after n years, it will be 112000*0.04^t-1

Answer 26

@triciaal my modeled equation is n(t)=112000e^0.04t

Answer 27

For b), it will be 112000 i0.04^(2004-1998)-1

Answer 28

@triciaal my t for part c is approximately 14. it does not equal 2008 if u add 14+1998

Answer 29

@triciaal what i do wrong

Answer 30

@triciaal it doesnt equal 2008

Answer 31

@Hoslos i used n(t)=112000e^0.04t

Answer 32

@klog23 https://www.youtube.com/watch?v=mhO9eL9Nuz0 check this out man, im pretty sure ull understand more quickly

Answer 33

(c) in what year will the population reach 200,000?
this means f(t) = 200000
set 0.04t + 112000 = 200000

Answer 34

sorry its not linear its exponential

Answer 35

@triciaal is my equation correct i used n(t)=112000e^0.04t

Answer 36

For c), make t subject of the formula in 200000=112000*0.04^t-1

Answer 37

@Hoslos im not using geometric progression im using exponentials

Answer 38

I thought that formula is also an exponential one.

Answer 39

@Hoslos our professor doesnt use that

Answer 40

Ok.

Answer 41

oh i got it the answer is 14 and its 2013 not 2008

Answer 42

great
14.495 so round up since it would be in the next year 1998 + 15 = 2013