## anonymous one year ago Suppose the population of trout in a certain stretch of a river is 4000. In about how many years will the population of trout be 700 if the decay rate is 35%? Use the equation 700 = (4000)(0.65)x and round the value of x to the nearest year.

1. anonymous

4 years

2. anonymous

how did you get that?

3. anonymous

(4000)(0.65)^4

4. anonymous

@arindameducationusc is that right? ^^^

5. anonymous

6. anonymous

internets lagging so having a hard time seeing responses

7. anonymous

no prob

8. anonymous

actually its 1 year 700=4000(0.65)^x 7000/4000=4000/4000(0.65)^x 7/4=(0.65)^x log(7/4)=log(0.65)^x 0.24=xlog(0.65) x=0.24/(0.187) x=1.28 x=1 year

9. anonymous

stuck between the 2 idk good luck

10. arindameducationusc

@lily1021 i am pretty sure ..thatz not the answer.

11. anonymous

hm okay so not 4

12. anonymous

@zzr0ck3r can you help with this?

13. zzr0ck3r

$$700 = (4000)(0.65)^x\\\dfrac{700}{4000}=0.65^x\\\ln(\dfrac{700}{4000})=\ln(0.65)^x=x\ln(0.65)\\ x=\dfrac{\ln(\dfrac{700}{4000})}{\ln(0.65)}\approx 4.04605$$ or $$700 = (4000)(0.65)^x\\\dfrac{700}{4000}=0.65^x\\\log_{0.65}(\dfrac{700}{4000})=\log_{0.65}(0.65^x)=x\\x\approx 4.04605$$

14. anonymous

so it is 4 years then

15. zzr0ck3r

Are you asking me if the closest whole number to $$4.04605$$ is $$4$$?

16. anonymous

well I'm just confused now because it was 4 then it wasn't then it was 1 then I tried it on my own and got 3 somehow. It really was a rhetorical question.

17. zzr0ck3r

you can check the answer by plugging it in...

18. zzr0ck3r

its always been 4

19. anonymous

But that was really unnecessary..

20. zzr0ck3r

lol

21. anonymous

It's not that funny. It was rude.

22. zzr0ck3r

they are not mutually exclusive

23. zzr0ck3r

It was meant to be funny. Sorry if you do not like my humor, focus on the math.

24. anonymous

Meaning and intent aren't the same thing, so oop @ you. I'm not bothered though.

25. zzr0ck3r

Meaning is actually synonymous to intent?

26. arindameducationusc

yes... @zzr0ck3r steps look good yes thats a confirmation @lily1021

27. zzr0ck3r

no need for confirmation. check your answers! If I am right, then $$4000*0.65^{4.04605}=700$$ Get your calculators out!!!

28. arindameducationusc

LOL

29. arindameducationusc

yes, you are right @zzr0ck3r

30. anonymous

Not really how something means to me isn't the same as how you meant something to be. English isn't my first language so maybe that's why you didn't understand.

31. anonymous

Just leave my question, it's done with.

32. anonymous

33. zzr0ck3r

I fully understand that you are being a baby. Just say thanks for the help and move on :) It was funny. I know you were not asking me to round it for you, but I wanted to point out that it was a weird question. Also your reply about not being sure because it was 1, then it was 4... did you think I would say, oh actually yeah I am wrong and that other dude is right?

34. zzr0ck3r

jokes again^^^

35. arindameducationusc

:D

36. arindameducationusc

k, guys i am going.... :)

37. anonymous

No you are being rude. So stop. You seem to be the one who can't move on. Like why are you still here? This is my question I politely ask you go away.

38. zzr0ck3r

I can not tell you anymore that I am joking. Also, the question is done. I solved it!!!

39. anonymous

And I cannot tell you anymore it wasn't funny. So get off my question if the question is done!!

40. zzr0ck3r

gn sorry :)

41. zzr0ck3r

And I assure you many people would think it was funny.

42. anonymous

Maybe pretentious douche bags who look down on people who are bad at math.

43. anonymous

44. zzr0ck3r

45. anonymous

lol

46. zzr0ck3r

there ya go:)

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