MAY11 Math SL P2 TZ2

[Ika Lob]

does anyone know how to do the last question of question 9. it was a probability question and its something about rolling a fair 4 sided dice 4 times max and getting a sum of 5 within 3 or more throws.

Yeah, you need to use binomialpdf on your calculator. There were 4 trials, the desired outcome had the probability of 4/16 and X=3 and 4.

Basically, you have to plug in your calculator Binompdf(4, (4/16), 3) and Binompdf (4, (4/16), 4) and the sum of the two numbers is the answer.

Were there 4 trials? Lol, what a stupid mistake for me to make oh well...

I made the exact same dumb mistake on the exam. Taking 5 trials.. that sum of 5 thing must have gotten me confused.

The number of trials = the number of times he rolled the dice. Don't remember what the question said, but if he rolled the dice 4 times, then yeah, the number of trials was 4.

[iber2011]

was it like 30% so its 0.3 but there isn't 0.3 so you get 0.7 and then from the tables you get the value of 0.7 but you put a negative sign. then you just put it in the equation and solve?? I hope you understand what i'm saying. i'm talking about the standard deviation question.

Edited May 6, 2011 by iber2011

[shreyaa]

Hey... Was the binomial probability answer 0.0508 ??????

[lighthuntz0r]

does anyone know how to do the last question of question 9. it was a probability question and its something about rolling a fair 4 sided dice 4 times max and getting a sum of 5 within 3 or more throws.

Yeah, you need to use binomialpdf on your calculator. There were 4 trials, the desired outcome had the probability of 4/16 and X=3 and 4.

Basically, you have to plug in your calculator Binompdf(4, (4/16), 3) and Binompdf (4, (4/16), 4) and the sum of the two numbers is the answer.

Ah, wasn't the question about the probability of getting a sum of 5 three out of four times? I can't believe I misread it

[IBMay2011]

This paper was okay, but a bit tough. It wasn't hard. Besides, we should have expected a somewhat "tough" paper because the first paper was extremely easy. The last question did indeed prove to be the toughest question in the paper, but this is IB: there is ALWAYS a question that looks new, i.e. has not been asked before, and thus is a bit tough. Cynthia, I wouldn't be surprised if the both of us get the same marks; we both think about questions the same way and have similar answers. As compared to the paper in November 2010, this was way easier. Overall, the whole paper was doable and no one should have had trouble with this. The vectors question was like a generous gift by the IB. This is what they always ask. It's in all papers. Everyone should have got that one right. Can't remember the others... I want to discuss questions you guys want to discuss. Good luck with chemistry on Monday because I know I'm terrified of the HL papers for that day.

[butters]

Hey... Was the binomial probability answer 0.0508 ??????

yea i remember getting the same answer!

ALSO, what GRAPH did you guys pick? I put graph 5, it was a guess though so im not sure that its corrent

Edited May 6, 2011 by Summer Glau
no text speak

[snarker]

I flunked.

[000]

I flunked.

i can't believe you are doing four Higher Level subjects. you must be dying.

[Kasper Jepsen]

I did alright, I think in total i'll get more in maths than i was planning for which is good

But this paper was harder than i thought. Section A went mostly fine but i could hardly answer any section B questions.

[patatat]

does anyone know how to do the last question of question 9. it was a probability question and its something about rolling a fair 4 sided dice 4 times max and getting a sum of 5 within 3 or more throws.

Yeah, you need to use binomialpdf on your calculator. There were 4 trials, the desired outcome had the probability of 4/16 and X=3 and 4.

Basically, you have to plug in your calculator Binompdf(4, (4/16), 3) and Binompdf (4, (4/16), 4) and the sum of the two numbers is the answer.

Your method seems right, but the logic I followed was finding binomcdf(4, (4/16), 2) and then subtracting that from 1. Both approaches seem identical in yield (too lazy to check with a calculator ).

[iber2011]

Guys please tell me how you answered the standard deviation question. Did you do it like how I did? I found the value of 0.7 from the tables then I put it in the equation with a negative value and solved for sigma.

[patatat]

In regard to the Paper itself, I found it relatively easy -- in fact, I probably did a little better on it than I did on Paper 1, which was not the case at all with my mocks. But I couldn't figure out how to approach the last question (TZ2), the one about the ferris wheel. I think I got some parts of it right, but most of it was guesswork. Could anyone explain, if they remember the question enough? I get the feeling it's something really simple that I overlooked, but then again, the question was pretty unfamiliar (which reflects my failure to study (enough) past paper questions).

Edited May 6, 2011 by Alphimeda

[Kasper Jepsen]

In regard to the Paper itself, I found it relatively easy -- in fact, I probably did a little better on it than I did on Paper 1, which was not the case at all with my mocks. But I couldn't figure out how to approach the last question (TZ2), the one about the ferris wheel. I think I got some parts of it right, but most of it was guesswork. Could anyone explain, if they remember the question enough? I get the feeling it's something really simple that I overlooked, but then again, the question was pretty unfamiliar (which reflects my failure to study (enough) past paper exams).

Well basically it was a trig function, with a period of 0-20. I couldn't remember how to find all the values though, so I missed the last 6 marks.

[Ika Lob]

does anyone know how to do the last question of question 9. it was a probability question and its something about rolling a fair 4 sided dice 4 times max and getting a sum of 5 within 3 or more throws.

Yeah, you need to use binomialpdf on your calculator. There were 4 trials, the desired outcome had the probability of 4/16 and X=3 and 4.

Basically, you have to plug in your calculator Binompdf(4, (4/16), 3) and Binompdf (4, (4/16), 4) and the sum of the two numbers is the answer.

Your method seems right, but the logic I followed was finding binomcdf(4, (4/16), 2) and then subtracting that from 1. Both approaches seem identical in yield (too lazy to check with a calculator ).

Yeah, exactly, that's another way to do it.

[Ika Lob]

Does anyone remember which topics the questions were on from 1-7?

I remember from paper 1 (1. Arithmetic, 2. Probability, 3. Vectors, 4. Derivative, 5. Natural Logarithms, 6. Statistics, 7. Matricies)

What about paper 2 (TZ2) ?

[patatat]

In regard to the Paper itself, I found it relatively easy -- in fact, I probably did a little better on it than I did on Paper 1, which was not the case at all with my mocks. But I couldn't figure out how to approach the last question (TZ2), the one about the ferris wheel. I think I got some parts of it right, but most of it was guesswork. Could anyone explain, if they remember the question enough? I get the feeling it's something really simple that I overlooked, but then again, the question was pretty unfamiliar (which reflects my failure to study (enough) past paper exams).

Well basically it was a trig function, with a period of 0-20. I couldn't remember how to find all the values though, so I missed the last 6 marks.

And you'd think the last part of the question would've steered me towards that, instead of confusing me even more well that makes sense, i.e. for the part with the chart values, you could have just plugged them into some kind of cosx function and so on. Or something along those lines, I think. Oh well

[patatat]

Does anyone remember which topics the questions were on from 1-7?

I remember from paper 1 (1. Arithmetic, 2. Probability, 3. Vectors, 4. Derivative, 5. Natural Logarithms, 6. Statistics, 7. Matricies)

What about paper 2 (TZ2) ?

All I can recall immediately is that one of the Paper 2 Section A questions was about the Binomial Theorem.

[000]

Does anyone remember which topics the questions were on from 1-7?

I remember from paper 1 (1. Arithmetic, 2. Probability, 3. Vectors, 4. Derivative, 5. Natural Logarithms, 6. Statistics, 7. Matricies)

What about paper 2 (TZ2) ?

All I can recall immediately is that one of the Paper 2 Section A questions was about the Binomial Theorem.

There was one with matrices where you had to find m and n where MX=N

then you had to solve the equation

[Ihavequestion]

HI everyone, how did math SL tz2 went in overall?

I found it quite easy, but i'm worried that it was good enough to make silly mistakes..

In paper 1 i did not understand the matrix inverse part, ;( which seemed pretty easy once you get what it meant..)

Part B was quite hard, easpecailly last question... (same in paper 2)

To me generally i should get least decent 5 out of 7 in each paper part A 1 and 2

but basically half rights in part B...

Im worried if the grade boundaries would be higher than last year..

I did so many silly mistakes which makes me nervous..

so i want to ask whats your general opinion about grade boundary this year? did it seem much easier than last year and seem to get high average?

I hope it would stay the same as last year which was 46 - 58 in overall grade to get 4.

Im feelin that i would get some where 45 - 50 marks in paper 1 and 40 to 44 in paper 2...

what do you think you will get in each papers??

[I`m Potato]

Does anyone remember which topics the questions were on from 1-7?

I remember from paper 1 (1. Arithmetic, 2. Probability, 3. Vectors, 4. Derivative, 5. Natural Logarithms, 6. Statistics, 7. Matricies)

What about paper 2 (TZ2) ?

All I can recall immediately is that one of the Paper 2 Section A questions was about the Binomial Theorem.

There was one with matrices where you had to find m and n where MX=N

then you had to solve the equation

I was kind of confused with that matrix question. Was the answer for part (b) and [c] the same? Except for [c] you don't write it in matrix form but as "x,y,z =" form?

Edited May 7, 2011 by I`m Potato