Worked solutions for Core, Number Patterns, Graphs & relations, and Matrices.

[xcookieFD]

if i just wrote "the 10th year" for the matrices question about in which year will the number of operators be less than 30...they'll probably take a mark off right?

[Will T]

Hey will. Just got a question for ya, for graphs and relation question 3 part (f) if i got part (i) wrong (for some reason got 23 phomes and 18 laptops) would i get consequentials for part (ii)??


So angry i got that wrong...

he is incorrect, 24 is outside the feasible reagion thus the point is (23,18)

I don't agree that (24,18) is outside the feasible region. Substituting those points into the inequality that they appear to be breaching yields: 35 x 24 + 50 x 19 < or = 1750. Which gives 1740 < = 1750 which is true. So those points should in fact lie in the feasible region.

[Will T]

if i just wrote "the 10th year" for the matrices question about in which year will the number of operators be less than 30...they'll probably take a mark off right?

Unfortunately for your sake, I suspect that they will. I saw something very similar in a Number patterns question on last year's exam where they wanted you to add a result to the starting year. So sorry but, yes I think you will be penalised for not writing the year.

[Jordzs]

if i just wrote "the 10th year" for the matrices question about in which year will the number of operators be less than 30...they'll probably take a mark off right?

Unfortunately for your sake, I suspect that they will. I saw something very similar in a Number patterns question on last year's exam where they wanted you to add a result to the starting year. So sorry but, yes I think you will be penalised for not writing the year.

Omg, I think I did the same thing!!

[kimk2kr]

Hey will. Just got a question for ya, for graphs and relation question 3 part (f) if i got part (i) wrong (for some reason got 23 phomes and 18 laptops) would i get consequentials for part (ii)??


So angry i got that wrong...

Funny you should mention that. I have a similar predicament as I wrote down 23 laptops and 19 phones. I can't be sure of what they'll do with consequential marks, but I hope it will be sufficient because otherwise I'm thoroughly screwed. I think for the last question, if you showed working out, at least 1 mark will be awarded. I guess the question is, how sufficient was your working out?

i think i did show sufficient working out. so might pull off a mark...

one thing i dont understand though, is that how is it 24? when i find the intersection between 35x + 50y <(=) 1750 and y<(=)(4/5)x i get x=23.3333333 and y=18.666667

so wouldnt it be 23,18 not 24 as its outside the given region?

[Will T]

Hey will. Just got a question for ya, for graphs and relation question 3 part (f) if i got part (i) wrong (for some reason got 23 phomes and 18 laptops) would i get consequentials for part (ii)??


So angry i got that wrong...

Funny you should mention that. I have a similar predicament as I wrote down 23 laptops and 19 phones. I can't be sure of what they'll do with consequential marks, but I hope it will be sufficient because otherwise I'm thoroughly screwed. I think for the last question, if you showed working out, at least 1 mark will be awarded. I guess the question is, how sufficient was your working out?

i think i did show sufficient working out. so might pull off a mark...

one thing i dont understand though, is that how is it 24? when i find the intersection between 35x + 50y <(=) 1750 and y<(=)(4/5)x i get x=23.3333333 and y=18.666667

so wouldnt it be 23,18 not 24 as its outside the given region?

(24,18) isn't outside of the feasible region, nor is (23,18). But in order to maximize it's better to produce that one extra phone. And so the answer will be 24 phones and 18 laptops. I suggest drawing this problem graphically and plotting the points (24,18) and (23,18) and you will have a better picture of what is going on in the question.

[kimk2kr]

Hey will. Just got a question for ya, for graphs and relation question 3 part (f) if i got part (i) wrong (for some reason got 23 phomes and 18 laptops) would i get consequentials for part (ii)??


So angry i got that wrong...

Funny you should mention that. I have a similar predicament as I wrote down 23 laptops and 19 phones. I can't be sure of what they'll do with consequential marks, but I hope it will be sufficient because otherwise I'm thoroughly screwed. I think for the last question, if you showed working out, at least 1 mark will be awarded. I guess the question is, how sufficient was your working out?

i think i did show sufficient working out. so might pull off a mark...

one thing i dont understand though, is that how is it 24? when i find the intersection between 35x + 50y <(=) 1750 and y<(=)(4/5)x i get x=23.3333333 and y=18.666667

so wouldnt it be 23,18 not 24 as its outside the given region?

(24,18) isn't outside of the feasible region, nor is (23,18). But in order to maximize it's better to produce that one extra phone. And so the answer will be 24 phones and 18 laptops. I suggest drawing this problem graphically and plotting the points (24,18) and (23,18) and you will have a better picture of what is going on in the question.

na i cant be bothered drawing the graph, haha

and because its a 3mark question (overall, both part i and ii), thinking that i gave enough working out, would i get 2/3? or would it still be 1/3...

[StumbleBum]

You really need to learn how to use

[Nima2703]

i dont understand the number patterns for houses not sold. It said how many were not sold? so hows that 29th - 18th? was that worth 2 marks?

It was worth 2 marks. Think of the sequence like this, by the time it gets to the 19th month, the amount of houses sold in that month would've been 60. The next month there will be 54, 48, 42 and so on. They're saying that after the 18th month, if they were to stop selling houses, how many will there be that should have been sold had it continued but will now not be sold. Essentially you have to add up all the numbers between 60, 54...... 12, 6, 0. And this gets you 330.

would i get 1 for working out?

[Will T]

You really need to learn how to use

Maybe some day. Originally when I was writing this I tried to, but it became too difficult.

[Will T]

i dont understand the number patterns for houses not sold. It said how many were not sold? so hows that 29th - 18th? was that worth 2 marks?

It was worth 2 marks. Think of the sequence like this, by the time it gets to the 19th month, the amount of houses sold in that month would've been 60. The next month there will be 54, 48, 42 and so on. They're saying that after the 18th month, if they were to stop selling houses, how many will there be that should have been sold had it continued but will now not be sold. Essentially you have to add up all the numbers between 60, 54...... 12, 6, 0. And this gets you 330.

would i get 1 for working out?

Quite possibly, I guess it would depend on where you went wrong?

[melvinpig]

For Graph's and Relations, the answer is (23,18) because (24,18) IS OUTSIDE the feasible region. If u equate the 2 equations on your CAS it turns out to be (23.33,18.67) and thats the max it can go to in the feasible region. Any Number in any x-coord or y-coord that is higher than that = it is outside the feasible region. The answer is (23,18) not (24,18)

[kimk2kr]

will you have not yet answered my question!

[Will T]

will you have not yet answered my question!

So you said the company should produce 23 phones and 18 laptops for part i, correct?
Well, that question is worth 2 marks, so I'm wondering if it will be 1 mark for the correct amount of phones and I mark for the correct amount of laptops. At any rate, 18 laptops is correct, but 23 phones is incorrect. So, if my prognosis of how they are going to score this question is correct you should get 1 mark for part i.
Now, for part ii. It's only worth 1 mark, so I'm wondering if they're only going to give out the mark if you have the correct answer. But, I think if you have correctly input your values for part i. into part ii. then you're showing that you know how to perform the computation that the question is asking you to do, and that your answer is only incorrect consequently because of a previous mistake.
If they're kind, then I think a lot of people will get the 1 mark for the last question, as showing how to use an objective function isn't too hard, and it would be a challenge to make a mistake whilst computing the answer (although I'm sure I'd find a way).

But that would make me think that they're going to be strict, and only award the mark for the correct answer.
At any rate, I think you've scored at least 1 mark, and quite possibly 2 marks for that section, provided they're going to be a bit generous with consequential marking.

[kimk2kr]

will you have not yet answered my question!

So you said the company should produce 23 phones and 18 laptops for part i, correct?
Well, that question is worth 2 marks, so I'm wondering if it will be 1 mark for the correct amount of phones and I mark for the correct amount of laptops. At any rate, 18 laptops is correct, but 23 phones is incorrect. So, if my prognosis of how they are going to score this question is correct you should get 1 mark for part i.
Now, for part ii. It's only worth 1 mark, so I'm wondering if they're only going to give out the mark if you have the correct answer. But, I think if you have correctly input your values for part i. into part ii. then you're showing that you know how to perform the computation that the question is asking you to do, and that your answer is only incorrect consequently because of a previous mistake.
If they're kind, then I think a lot of people will get the 1 mark for the last question, as showing how to use an objective function isn't too hard, and it would be a challenge to make a mistake whilst computing the answer (although I'm sure I'd find a way).

But that would make me think that they're going to be strict, and only award the mark for the correct answer.
At any rate, I think you've scored at least 1 mark, and quite possibly 2 marks for that section, provide they're going to be a bit generous with consequential marking.

thanks will! youre a champ! <3

hopefully theyre generous enough to give out a mark haha

like last year, for bearing questions they gave a mark for writing 79 or something rather than having to write  079T which I personally think would be the only correct answer haha