Multiple Choice - Answers (1 Viewer)

[Lazarus]

This is what I've come up with for the multiple choice questions - any disputes?

1. D
2. B
3. C
4. B
5. A
6. A
7. C
8. D
9. D
10. B
11. C
12. D
13. D
14. A
15. B
16. C
17. B
18. C
19. A
20. B
21. D
22. C

Update: In light of recent disputes.
Update: Answer for Q4.
Update: Answer for Q18.

 

[SparklingDimond]

Hmm i got all the same except for the two i didnt really understand: q.7 and q.21. For 7 i got c and for 21 i got a. Oh and for 20 i got a. im not sure if it could be 1/3 cause it says rob and alex are EACH twice as likely to win.

 

[Lazarus]

I agree with you about Q7, I think it should be C.

Q20:
x = probability that Tan wins
y = probability that Rob wins
z = probability that Alex wins

x + y + z = 1
x + 2x + 2x = 1
5x = 1
x = 1/5


Q21:
Area of Jenny's sheets is 0.21 * 0.3 = 0.063 m². This means that (1/0.063) of her sheets make up a full square metre.

Therefore the mass of one of her sheets is 80 / (1/0.063) = 5.04 grams.

And so the number of sheets she has is given by 25200 / 5.04 = 5000.

 

[SparklingDimond]

Oops I did get b for 20! Thanks for the working for 21, I don't know why I didn't get that one, i went over about 4 times too! Anyone know about q.7?

 

[princess b*]

yep, those corrections are right. i had the same answer for the financial expectation q as well.

only thing, for Q.4 i had D but i think it was wrong.
rates never equal $100 000+, so i think u were sposed to do:
($377 000 x 0.272950)/ 100 + $195. came to answer B.
i could be wrong but me dads a maths teacher and he reckons thats right.

 

[princess b*]

Q. 15 & 16

anyone got the working for Q. 15 & 16?

 

[nomza]

....20/22 -- not too bad I guess considering I suck at maths.

16)

13=2y(p3)-1
14=2y(p3)
y(p3)=7

y=7(cube root)

 

[Lazarus]

Hmm I guess I should include working in the final set of solutions too. Damn. OK.

15)

A_n denotes the amount of the annuity at the end of the nth year.

A₁ = 1200

A₂ = A₁(1.05) + 1200
A₂ = 1200(1.05) + 1200

A₃ = A₂(1.05) + 1200
A₃ = (1200(1.05) + 1200)(1.05) + 1200
A₃ = 1200 + 1200(1.05 + 1.05²)

A_n = 1200 + 1200(1.05 + 1.05² + ... + 1.05ⁿ)

.'. A₁₀ = 1200 + 1200(1.05 + 1.05² + ... + 1.05⁹ + 1.05¹⁰)


The sum inside the parentheses forms a geometric series.

S_n = a(rⁿ - 1) / (r - 1)
S₉ = 1.05(1.05⁹ - 1) / 0.05
S₉ = 11.57789254...

A₁₀ = 1200 + 1200(11.57789254...)
A₁₀ = 15093.47...

A₁₀ ~ $15093

 

[princess b*]

thanks for q. 16 nomza

 

[princess b*]

thanx heaps laz

 

[bugger]

Thanks a lot

I have a problem with question 15...i believe it should be B

the formula is

n = M ( (1 + r)n - 1
-----------------
r (1+r)n

or

(1 + 0.05)10 1
------------------- x 1200
0.05 (1 + 0.05)10

= 9266.08

 

[nomza]

Yeah I know bugger, that's totally what I got.....

BUT if you think about it, if he has deposited $1200 for ten years he HAS to have at least over $12 000

 

[jennals]

I agree with you there bugger.

I think C is the answer for the future value of an annuity...

When you're finding the present value, aren't you finding the value of the lump sum that will give you the same value as an annuity that has regular contributions?

I don't think I made sense there...

 

[Lazarus]

Yes, you're correct - I calculated the future value of the annuity, not the present value.

The answer is B.

 

[nomza]

are you serious???????


YAY -- I got 21/22 -- The best I've ever done in General, hell yeah!!

 

[tammer]

okay so

q4. did anyone else figure a problem
i believe the answer is B

the 0.272950 is cents in the dollar
so therefore it is:

0.272950/100 x $377000 + 195

my calculations come to 1224.02

which is B

i got B in the exam (dammit) but redid it and got this

so what is the correct answer for 15. i think it is B

i also believe q21. is A

area of one page is 630cm^2
this is 63% of 1m^2

63% of 80 grams is 50.4g 25200g/50.4g = 500 (=A)

 

[tammer]

and laz... can i be a real pain in the butt and ask for working on q18. i suck at this sorta stuf

 

[Lazarus]

Yeah, I think you're correct with Q4, tammer, it should be B (sheesh).

We decided that Q15 was B.

With your working for Q21, it's actually 6.3%, not 63% (100cm * 100cm = 10000cm²). Fairly certain the answer is D.



Working for Q18:

P(winning 1st prize) = 1/200
P(winning 2nd prize) = 1/199

(1/200 * $100) + (1/199 * $50) - $1
= 1/2 + 50/199 - 1
= -99/398
~ -0.25

 

[nomza]

......I got D for 4

 

[tammer]

hehe laz you're right with 21 being D. damn i thought i was all smart coz it took me so long to figure out - crap! oh well so i ended up with 19 out of 22. not so good.