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Section II (1 Viewer)

mulimulix

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Perimeter of a circle - arc length formula

(2*pi*13) - (130/360 * 2*pi*13)

= 52. 16
But this doesn't take into account the part of the perimeter which has been created. You still need to add two lots of the radius, as there are lines leading into the circle; it isn't just empty space.
 

wavess

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With this question: image.jpg
Am it right?

T/60 = 120/30
T= 120/30 x 60
T= 240
= 240 x11%
= 26.4
= 240- 26.4
= 213.60

Did the same method in exam but I can't remember my actual answer
 

harro619

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For this one, did anyone get 270, because you divide 240 by 0.89?
 

drh94

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I actually feel really good about section II, except for the vanishing points, which I now know I did wrong...

The last question about populations I think was the easiest and If you were logical it was simple to gain marks.

The shadow question threw me for a while but in the end i worked out the angle of the line and then used trig, gave me a plausible answer.

Finished with 15mins to spare :spin:
 

drh94

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With this question: View attachment 26813
Am it right?

T/60 = 120/30
T= 120/30 x 60
T= 240
= 240 x11%
= 26.4
= 240- 26.4
= 213.60

Did the same method in exam but I can't remember my actual answer
You'll get some marks for it but in the end multiplying 240 by 111% would give the 2008 amount due to the seal species dying off slowly.
so 1.11 x 240 = 266.4
 

Study-Guy

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You'll get some marks for it but in the end multiplying 240 by 111% would give the 2008 amount due to the seal species dying off slowly.
so 1.11 x 240 = 266.4
You cant multiply by 1.11 because thats using 11% of 240 which is wrong. You had to divide by 89 and then multiply by 100 giving an answer of 270 (to the nearest seal :p)
 

Study-study

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did anyone else just draw a giant cube for the vanishing point question? LOL
 

jayq94

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for the capture recapture question i went,

240/100 x 111 = 266.4
 

ajay_sneaky14

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Re: General Thoughts: General Mathematics

not really if u think about it closely enough
 

dyS htN

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Re: General Thoughts: General Mathematics

I only knew the vanishing point thing because of being an art student; You get taught about it when you're learning to draw buildings. It's the term they use to describe the way that all lines around you seem to head towards a single point, due to your perspective, if that makes sense.

Other than that, I didn't find it desperately hard and the bit of study I did really helped. I really enjoyed doing the estimate the seal population thing for some reason...
Trig will be my downfall; I didn't like the shadow thing.
That looks right. But I seem to remember the cube having parallel lines. If you use the two vanishing points in this diagram, the lines are not parallel. Am I missing something?????
 

poich

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Re: General Thoughts: General Mathematics

You had to use trig to find the top left angle. tan-1(3/2.5). Once you have the angle you can use the sin rule to figure out the whole length, then u minus the 3 meters. I think the answer was 1.8m
i also got 1.8
similar triangles. used guess and check haha
becaused 1.8/4.8 is the same ratio as 1.5/4

anyone work it out another way? (FLAGPOLE QUESTION)
 

harrietty

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You cant multiply by 1.11 because thats using 11% of 240 which is wrong. You had to divide by 89 and then multiply by 100 giving an answer of 270 (to the nearest seal :p)
I don't think so... I just did the question then and I got 266.4, which to the nearest seal would be 267 seals? ... 11% of 240 is right, isn't it? :)
 

harro619

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I don't think so... I just did the question then and I got 266.4, which to the nearest seal would be 267 seals? ... 11% of 240 is right, isn't it? :)
No, because its not 11% of 240, it is 11% of the 2008 seal population. 240 is 0.89 of 270 (11% less).
 

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