Maths Competition (1 Viewer)

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munkaii said:
Woohoo! Is the answer for the L Shaped cake 100? Its a shame i wrote 75 because i miscalculated..
Nope, 80

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munkaii

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Really? I calculated the trapezium + triangle area to be 200 total. Therefore diving through by 2 to give 100. And the larger triangle ended up being 200.
 

Slidey

But pieces of what?
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I think it was far easier (and more enjoyable) than last year's.
 
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munkaii said:
Really? I calculated the trapezium + triangle area to be 200 total. Therefore diving through by 2 to give 100. And the larger triangle ended up being 200.
I'm not sure I follow. You're saying the bottom left piece has area 200, and the others have areas which sum to 200, so the smaller of them must be 100?

a + b = 200 does not necessarily mean that min(a,b) => 100

Is this what you mean?
 

munkaii

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Consider this diagram, using the L shaped corner as a pivot point to rotate ur cut until you get the two smaller pieces almost identical.
 
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munkaii said:
Consider this diagram, using the L shaped corner as a pivot point to rotate ur cut until you get the two smaller pieces almost identical.
Ok, I see what you mean now. The problem with that is that when you rotate that diagonal line around the L-shaped corner, the area of the big bottom-left piece does not stay constant. When the two smaller areas are equal, the gradient of the line is -2.5, and both smaller areas are equal to 80.
 

munkaii

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Edit: Oh i see my point of error. If its 100, then it means the bottom right forms a square.
 

3G'sMt5:16

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how about.. b^2-4ac is delta the discriminant... sorry just BORED lol

oh ohhh and ermm... if:

* b^2-4ac > 0 then theres 2 roots or destinct roots
* b^2-4ac = 0 theres only one root or equal loots.. lol loots
* b^2-4ac < 0 then NO REAL ROOTS (unreal number =)
* b^2-4ac < 0 and a>0 then it is a pos. def
* b^2-4ac > 0 and a<0 then it is a neg. def

yarrrr
 

Trebla

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I got 63/120 for Maths Comp. That miraculously equates to a distinction! WHOA! I only just passed (at 52.5%) and got top 4% of the state! I think the cut off for distinction was like 50/120!!!!!!! Wah that's low......!!! I think 70+/120 got high distinction.
Wow, that test was really hard and challenging for everyone and I thought it was just me screwing up......
What did you guys get?
 
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Trebla

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We got the Maths comp certificate/results recently last week.
After asking a few peers what they got, I deduced where the cut offs for distinction and high distinction might be.
 

Dumsum

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My teacher said I got a credit. This after pulling 1st in the state for the UNSW comp. lol. I'm so random
 

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