Sunday, August 21, 2011

Answers - Maths Practice Paper 7a

Answers for 7a:
1.   3
2.   2
3.   2
4.   1
5.   2

6.   3
7.   2
8.   2
9.   4
10.  1

11.   3
12.   2
13.   2
14.   1
15.   4

16.  428.15
17.  0.25 or 1/4
18.  5
19.  1/10
20.  (3p +  12)  or  3(p + 4)

21.  2.25 or 2 1/4
22.  45°
23.  SE / South-East
24.  180
25.  (3p - 4)

26.
 3 units ® $8.40                             
4 units ® $ 11.20
$11.20  +  $5  =  $16.20                   [M1], [A1]


27. 28


28.  100 – 81  = 19                                   [M1]
        19/ 100  =  19%                                [A1]


29.  
ÐDAB  =  120°   ÐYAB  =  140°   
ÐAYZ  =  180° – 140°              [M1]
            =  40°                 [A1] or [A2]

30.

10%     ®     8                      
210%   ®    168                    [M1], [A1]
Posted by at
Labels:

9 comments:

  1. AnonymousAugust 21, 2011 at 12:47 PM

    Hi - Could someone pls post the working for Q28 - I am unable to get the answer. Thanks in advance.

    ReplyDelete
  2. DeveshAugust 21, 2011 at 5:14 PM

    Isn't this the document you sent us? How come it's here?

    P.S. The symbols are a bit weird. It's that lousy ASCII coding again.

    ReplyDelete
  3. DeveshAugust 21, 2011 at 5:20 PM

    Symbol Conversion Guide:

    ® = right arrow sign (if this doesn't come up weird this time, it's )

    Ð = Angle sign ()

    [number]/[number] (e.g. 19/100) = numerator/denominator

    ReplyDelete
  4. AnonymousAugust 22, 2011 at 2:37 PM

    How to get the answer for qn 28? Could someone explain please?

    ReplyDelete
  5. AnonymousAugust 23, 2011 at 1:23 PM

    Hi Mdm Toh - the first anonymous comment re Q28 - was from me - Devesh's mother. Second one was not me. Was instructed by Devesh to own up to the comment :-). But seriously - we did not get the answer as the pattern does not go up exponentially - which would be required for pattern 9 to use 81% of the chips. So obviously I am missing something.

    Mrs Logendran

    ReplyDelete
  6. ParkBom SuGarheartZAugust 23, 2011 at 4:43 PM

    I think 81 was from 9 times 9. I am not too sure as well...

    ReplyDelete
  7. AnonymousAugust 23, 2011 at 7:19 PM

    pattern 5-5×2=10
    10-1=9
    pattern6-6×2=12
    12-1=11
    pattern7-7×2=14
    14-1=13
    Pattern 8-8×2=16
    16-1=15
    Pattern 9-9×2=18
    18-1=17
    (Pattern 1 to 9)1+3+5+7+9+11+13+15+17=81
    100-81=19

    (19÷100)×(100÷1)=19%

    ReplyDelete
  8. AnonymousAugust 23, 2011 at 7:37 PM

    O no. In a prime example of careless mistakes - I failed to realise that it is cumulative use of chips. Got the pattern right - but did not add them all up. Lesson in how it is important to read the question properly! Thanks to whoever posted the solution.
    Mrs Logendran

    ReplyDelete
  9. AnonymousAugust 23, 2011 at 7:59 PM

    I got the answer wrong too..So, thanks to whoever helped me understand the question.
    Bhairavi Buddhamurthy

    ReplyDelete

Subscribe to: Post Comments (Atom)