Australian Maths Competition (7 Viewers)

[RealiseNothing]

Re: Australian Maths Competition 2013

challenge is to solve the dart question when 3 is replaced by n

 

[FBJ]

Re: Australian Maths Competition 2013

your denominator is wrong...but i think it was typo

 

[FBJ]

Re: Australian Maths Competition 2013

and how do you do that sphere question, coz couldn't the plane go almost anyway, so hard to calculate hahaha

 

[RealiseNothing]

Re: Australian Maths Competition 2013

your denominator is wrong...but i think it was typo

Yep, fixed.

 

[RealiseNothing]

Re: Australian Maths Competition 2013

and how do you do that sphere question, coz couldn't the plane go almost anyway, so hard to calculate hahaha

I'm not sure how correct my method is, but I considered the ratio of the volumes first (1:8). From here, I tested each of the answers. For example (c) was 1:3, which means the smaller sphere would have been divided into quarters so to speak (1 quarter and 3 quarters). Then from here I multiplied by 8 or something and tried to see which ratio seemed like it would work.

 

[hayabusaboston]

Re: Australian Maths Competition 2013

I'm not sure how correct my method is, but I considered the ratio of the volumes first (1:8). From here, I tested each of the answers. For example (c) was 1:3, which means the smaller sphere would have been divided into quarters so to speak (1 quarter and 3 quarters). Then from here I multiplied by 8 or something and tried to see which ratio seemed like it would work.

I combined their volumes and considered individual volume ratios with 1:8, ended up with 1:3

 

[Makematics]

Re: Australian Maths Competition 2013

yeh i did the probability one doing cases based on where the first shot hit. in total there should have been cases, but i fkn missed one in the exam which is why my answer was off -.- eff... and yes i know i overcomplicated.

 

[Makematics]

Re: Australian Maths Competition 2013

realise do you have the paper?

 

[RealiseNothing]

Re: Australian Maths Competition 2013

realise do you have the paper?

Nope.

 

[RealiseNothing]

Re: Australian Maths Competition 2013

Prime factorisation is

Just saying, for question 20 which was "how many ways can 2013 be expressed at the sum of two or more consecutive integers", this basically gave you the answer.

 

[AnimeX]

Re: Australian Maths Competition 2013

Just saying, for question 20 which was "how many ways can 2013 be expressed at the sum of two or more consecutive integers", this basically gave you the answer.

care to explain?

 

[RealiseNothing]

Re: Australian Maths Competition 2013

care to explain?

The amount of ways a number can be expressed as the sum of consecutive integers is the product of the powers of it's prime factors plus one respectively.

 

[Crazylo0pwhole]

Re: Australian Maths Competition 2013

What was the solution to Q28? I wanna check i tried to get that one.

 

[Web Addict]

Re: Australian Maths Competition 2013

The amount of ways a number can be expressed as the sum of consecutive integers is the product of the powers of it's prime factors plus one respectively.

Wtf? Can you please provide an example?

 

[Crazylo0pwhole]

Re: Australian Maths Competition 2013

Wtf? Can you please provide an example?

I think for example 2013 (1x1x1)+1= 2 ways of expressing as a sum of consecutive integers? correct me if i'm wrong

 

[jihad1234]

Re: Australian Maths Competition 2013

Hi, does anyone have the questions for the Junior Division paper - last 5 questions? My brother is freaking out because he didn't manage to finish the last 5 and he wants to see whether they were as hard as he expected...if anyone can provide the last 5, it would be greatly appreciated.

 

[iBibah]

Lol not sure everyone knows, but not everyone does the maths comp on the same day.

 

[hayabusaboston]

Re: Australian Maths Competition 2013

Yay ibibah, lets spread the answers to all the questions and bias the results for other kids!
Good idea
Pump up dat HD quantity around australia.

 

[RealiseNothing]

Re: Australian Maths Competition 2013

Yay ibibah, lets spread the answers to all the questions and bias the results for other kids!
Good idea
Pump up dat HD quantity around australia.

Not sure why you think that's possible.

 

[RealiseNothing]

Re: Australian Maths Competition 2013

Lol not sure everyone knows, but not everyone does the maths comp on the same day.

I confirmed with carrot that it was ok to post solutions before I posted any.