# Exponential graphs Help!!

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Thread starter 6 months ago
#1
the size of the red squirrel population has decreased exponentially the rate of the decrease is 15% at the start of 2016 there were 10000 estimated in the UK. Estimate the size of the population of the red squirrels in the UK at the start of 2010. to 3s.f

- i saw another post with this question and they got 85 as the base but i need some help with how to get that number
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6 months ago
#2
Don't overthink the word "exponentially". Think in terms of a compound percentage situation.
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6 months ago
#3
(Original post by lunathefighter)
the size of the red squirrel population has decreased exponentially the rate of the decrease is 15% at the start of 2016 there were 10000 estimated in the UK. Estimate the size of the population of the red squirrels in the UK at the start of 2010. to 3s.f

- i saw another post with this question and they got 85 as the base but i need some help with how to get that number
If there is a 15% decrease in a population then the size of the population left is the old population multiplied by 0.85.
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1 week ago
#4
uh soo all i did was 100-15 which gave me 85 and then i divided it by 100 which gave me my multiplier which is 0.85 however i got the answer of 3771.495156 but its not working andd did round it to 3 sf after and it didnt workk

oKAY SO I GOT THE ANSWER ALL IM TELLING U IS TO READ THE QUESTION PROPERLYYYY
Last edited by bahahhahha05; 1 week ago
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1 week ago
#5
whats the answer i really need it please
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1 week ago
#6
hey i really need the answer please before tomorrow
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1 week ago
#7
Hi everyone, I have a similar problem of the answer not being correct. This is what I did...I first did 100 - 15 = 85% (because it is decreasing so you take-away)then I did 85 / 100 = 0.85From 2010 to 2016 it is 6 years so I made an equation of p x 0.85^6 = 10,000to get p I did 10,000 / 0.85^6 (this part I would do use a calculator) which gives me 26514.6834 and I rounded to 3 significant figures which is 265 right? That's my answer, 265. Can someone please please please tell me if this is correct otherwise if this is wrong please tell me the correct answer because then at least I can see where I went wrong and I would do the question again to get the answer.
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1 week ago
#8
Ok so I just looked at the question again and I also realised that I DID NOT READ THE QUESTION PROPERLY. It says 3sf right?. Well I didn’t give it to 3sf tbh. My answer I got was 265 but actually it’s meant to be 26500 to replace the numbers 14 in 26514.6834 if you get what I mean. So to those of you struggling it’s probably you not reading the question properly or not giving the answer properly. But there you go, the answer was 26500 squirrels.
Last edited by habis080.316; 1 week ago
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