***2015 JC Maths Paper 1 - all levels - June 5th 2015***

james_jog99

Found the paper easy as hell. Was finished after 1 hr and had the next 90 mins to look back. The only question I had slight trouble bit was the second part of tax one where you were working backwards and ended up just doing trial and error until I found it. I'm pretty sure I got at least 90% and I'm hoping for 95%+ (I know they don't tell you the percent) as I am planning to do mainly maths subjects for LC as I like it.

PS I had studied the Fibonacci sequence (last question) in maths enrichment classes so that was extremely easy for me.

Well I hope I can do well in p2 to back up that solid p1 performance!

james_jog99

patrickLouth1 wrote: »

HL- I am very confident i got an A on that paper
Does anyone know the solution for
Explain why t100=t98 + t97

Consider it this way. If at first I go up one step I am at step 99 and from there every way I can do it will be in t99 cuz it's like I am starting from the 99th step, but if I go up 2 steps the same principal will apply but for t98. Therefore t98 + t99 = t100 because you can only go up either 1 or 2 steps to start with.

UnknownEntity

james_jog99 wrote:

Found the paper easy as hell. Was finished after 1 hr and had the next 90 mins to look back. The only question I had slight trouble bit was the second part of tax one where you were working backwards and ended up just doing trial and error until I found it. I'm pretty sure I got at least 90% and I'm hoping for 95%+ (I know they don't tell you the percent) as I am planning to do mainly maths subjects for LC as I like it.

This is how you do that gross wage question.

Gross wage: x
Standard tax: 6760
Higher tax: 0.4(x-33,800)
Tax credits: 3300
Net wage:34,780

x-6760-(0.4x-13,520)+3300=34,780
0.6x=34,780+6760-13,520-3300
0.6x=24,720
x=41,200

That is the correct answer because: (41,200-33,800)x0.4=2960
2960+6760=9720
41,200-9720=31,480
31,480+3300=34,780 which is her net profit that was given in the question.

james_jog99

haiyna wrote: »

This is how you do that gross wage question.

Gross wage: x
Standard tax: 6760
Higher tax: 0.4(x-33,800)
Tax credits: 3300
Net wage:34,780

x-6760-(0.4x-13,520)+3300=34,780
0.6x=34,780+6760-13,520-3300
0.6x=24,720
x=41,200

That is the correct answer because: (41,200-33,800)x0.4=2960
2960+6760=9720
41,200-9720=31,480
31,480+3300=34,780 which is her net profit that was given in the question.

Thanks for posting that. I ended up just using the process from part one like ten times but I did get 41,200 as my answer so hopefully I'll get the marks.

UnknownEntity

james_jog99 wrote:

Thanks for posting that. I ended up just using the process from part one like ten times but I did get 41,200 as my answer so hopefully I'll get the marks.

Well you must have done something right because that is a very hard number to get to by chance!

gj kg hjjjj

how to
do question 4 pls?

UnknownEntity

A: 3(7)+5
21+5
26

B: 3K+5

C: 3K+5=K
2K=-5
K=-5/2

Hope that helps!

james_jog99

gj kg hjjjj wrote: »

how do question 4 pls?

i) f(7) = 3(7) + 5
F(7) = 26

ii) f(k) = 3(k) + 5
F(k) = 3k + 5

iii)
F(-3) = -4
F(-2) = -1
Therefore it's between -3 and -2
F(-2.5) = 3(-2.5) +5
F(-2.5) = -7,5 + 5
F(-2.5) = -2.5

gj kg hjjjj

Any one know the question with the simultaneous equations?

gj kg hjjjj

james_jog99 wrote: »

i) f(7) = 3(7) + 5
F(7) = 26

ii) f(k) = 3(k) + 5
F(k) = 3k + 5

iii)
F(-3) = -4
F(-2) = -1
Therefore it's between -3 and -2
F(-2.5) = 3(-2.5) +5
F(-2.5) = -7,5 + 5
F(-2.5) = -2.5

Did you do the paper today?

gj kg hjjjj

gj kg hjjjj wrote: »

Any one know the question with the simultaneous equations?

No I'm talking about the one with b and c question 12

Kbvdpo

How was q13 done?

Also was is right to answer t100=t99 + t98 with:

T3 = t2 + t1
3=2+1
3=3

james_jog99

gj kg hjjjj wrote: »

Any one know the question with the simultaneous equations?

i)
You know h(1) = 5 so you know 2(1)^2 + b(1) + c = 5 so that's equation 1 which when worked out is b + c = 3
Repeat for h(2) = 13 and you will end up with equation 2 which is 2b + c = 5

ii)
Times equation 1 by -1 so the c's cancel and you get b= 2. Now you can fill b=2 into and equation above eg (2) + c = 3 and you get c= 1 which are the answers for the question

james_jog99

Kbvdpo wrote: »

How was q13 done?

Also was is right to answer t100=t99 + t98 with:

T3 = t2 + t1
3=2+1
3=3

It says explain so they might have wanted more but I say you still got a big chunk of the marks at the very leastand for q)13 for a) you just moved the y value up 2 units and for b) you timesed it by minus 1 eg if the og line is at y=4 then b) is at y=-4

patrickLouth1

haiyna wrote: »

I got 3k+5=k
2k=-5
K=-5/2

I got the same thank you

gj kg hjjjj

Do you still get marks for the right answer without workings

Kbvdpo

james_jog99 wrote: »

It says explain so they might have wanted more but I say you still got a big chunk of the marks at the very leastand for q)13 for a) you just moved the y value up 2 units and for b) you timesed it by minus 1 eg if the og line is at y=4 then b) is at y=-4

Thanks!👍 I did write down a lot of words aswell, they made sense at the time but I don't remember what they were now!
Thanks, I think that's what I did but I wasn't sure if it was right!
Did you do the paper today? What did you think? I thought it was great! If paper 2 is going to be anything like then I'll be hoping for a good grade! Got a b in the mocks & they were far worse than that paper today!

bearwhite

For the last bit in question 14 I took a shot in the dark and said it was exponential...

UnknownEntity

Kbvdpo wrote:

Thanks!👠I did write down a lot of words aswell, they made sense at the time but I don't remember what they were now! Thanks, I think that's what I did but I wasn't sure if it was right! Did you do the paper today? What did you think? I thought it was great! If paper 2 is going to be anything like then I'll be hoping for a good grade! Got a b in the mocks & they were far worse than that paper today!

If paper 2 is ANYTHING like paper 1 then we will be one very lucky bunch indeed!

james_jog99

gj kg hjjjj wrote: »

Do you still get marks for the right answer without workings

Very little to none. The main focus of the exam is to see if you can find out how to do the question that's why attempt marks are a thing.

gazump123

james_jog99 wrote: »

It says explain so they might have wanted more but I say you still got a big chunk of the marks at the very leastand for q)13 for a) you just moved the y value up 2 units and for b) you timesed it by minus 1 eg if the og line is at y=4 then b) is at y=-4

Do you not draw the line in the opposite direction as the slope would be multiplied by -1 as well?

james_jog99

gazump123 wrote: »

Do you not draw the line in the opposite direction as the slope would be multiplied by -1 as well?

When you multiply it by minus one the slope changes eg y=2 will become y=-2 so the slope will be 1/2 rather than -1/2 in the original

gazump123

james_jog99 wrote: »

When you multiply it by minus one the slope changes eg y=2 will become y=-2 so the slope will be 1/2 rather than -1/2 in the original

Good that's what I did.

patrickLouth1

Roughly how many marks were going for the symitanius equation today?
They are usually 10 arnt they
Also,what on the mobile data what did y'all answer for the last part

james_jog99

patrickLouth1 wrote: »

Roughly how many marks were going for the symitanius equation today?
They are usually 10 arnt they
Also,what on the mobile data what did y'all answer for the last part

I'm not 100% sure what marks go for the questions but it's usually either 10,15 or 20.
As for the mobile data part, I said that it allows Ferg to see at what amount of mbs downloaded is it cheaper to go with the other mobile company and will let him find out which plan is cheaper for him. This is what I said generalised but I waffled for a good bit to make my answer longer.

patrickLouth1

HL What did everybody get for them two inequalities on the paper?

frans123

(A)2<=n<=4
b) both 0

patrickLouth1

frans123 wrote: »

(A)2<=n<=4
b) both 0

Got the same
For the second one ,i had both of them 1 i changed it last second
Would 1 still be correct

carefulnowted

patrickLouth1 wrote: »

Got the same
For the second one ,i had both of them 1 i changed it last second
Would 1 still be correct

I also changed mine to 1, I think that any number would have been correct as long as the same number was in each box

patrickLouth1

carefulnowted wrote: »

I also changed mine to 1, I think that any number would have been correct as long as the same number was in each box

Thats what i was thinking,what did you get for q13plotting the 2 graphs