Leaving Cert '11/'12 Off-Topic 2

I find everything in HL maths spectacularly difficult.

Is it wrong to say that I actually like some of the Maths course now because I understand it? :pac: Yeah? Ok..

The internet is literally all that stands between each of us, and 625 points. :L

JonnyMcNamee wrote: »

Think I might fly on over to the Cuckoo's Nest for a little ban.. Otherwise I'll just end up spending the next whatever is left on this :pac:

Sadly I think the ban only extends to the Cuckoo's Nest forum. PM a Mod and they'll sort ya out anyway

Yeah, it seems simple but my brain imploded thinking about it. It might be a bernoulli trial but i really dont know :L

Just back from work and I am completely wrecked.
Chemistry questions and a Spanish essay to be done.. Lets get this party started!!

Togepi wrote: »

I'm so confused. :pac:

I did it like this:
You want the probability of two coming up. So that's, one and another again. The probability of getting one is 5/8 and another one is 4/7.
Since it's one and another you multiply them and that's how I got 35.7%.

Well if it's at least what I'd do is add up the probability of getting 2,3 or 4.
So that's .357 + .1786 + .071 which is .607 or 60.7%

That doesn't seem right either

If you study 5 the probability of 1 coming up is 1- it's definite. The probability of another one coming up is 4/7. So you've got 1x4/7. That means there's a 57% chance you'll have a choice on the paper.

Togepi wrote: »

Any idea what the probability of having either 2 or 3 or 4 of your 5 poets coming up is?

I think Eathrin is right with 98%, that's what I'm getting too.

edit: Aagh but it's so confusing

Wait now I think it could be 97%. Anyway, I think basically if you study 5 it's very unlikely you won't have at least 2, as all 3 of the ones you didn't study would have to come up.

Hmm. If you study ONE poet, you have a 50% chance of them coming up. Study two poets and you have a 79% chance one will come up. I probably shouldn't say that though....

PictureFrame wrote: »

How are you so good at Maths finality? Were you always good in like Primary School or whatever? I'd love an auld Mathsy brain.

I'm NOT good at probability to be honest. :L It's so confusing.
I have always liked maths, but I've only really loved it since 5th year. I think that's because in primary school and junior cert if I was finished the questions we were doing or whatever early, I'd end up waiting and though I know it sounds petty, I think that actually put me off the subject a little bit. The teacher I have for leaving cert is amazing, she let me work ahead and teach myself since almost the start of fifth year, so I ended up doing a LOAD of maths all the time because I genuinely found it fun, I'd do every question in the book until something made complete sense to me. Then I started getting between 95 and 100% in class tests whereas in junior cert I would've been getting high Bs/low As. Half way through fifth year I banned myself from doing maths after school. :L
I wish I were better at maths, I think I'd be lost if I studied pure maths in college.

So that's my maths life story. What about everyone else, how did you find maths all your lives? :P

Eathrin wrote: »

Okay so this can be done if we multiply 5/8 x 3/7 x 2/6 x 1/5
Obviously order doesn't matter to us so we multiply this by 4.

But surely because one poet coming up is definite, you can just leave that out entirely and treat it as if you've studied 4 out of 7, where 3 poets will come up. Oh god why so confusing.


edit: there are 35 possible ways of choosing 3 from 7. Only one of those will be all 3 you haven't studied.1 - 1/35 = 97%

if you do 1 - (3/7 x 2/6 x 1/5) this gives you the same thing.

My final answer is 97. Haha. At the end of the day it's between 93 and 98%. :L

I am totally asking my maths teacher this tomorrow :L