Q&A - PSLE Math

[imacsg]

http://www.flickr.com/photos/52713803@N03/4859718213/



http://www.postimage.org/image.php?v=aVjrqdi

[tianzhu]

imacsg:

http://www.flickr.com/photos/52713803@N03/4859718213/

Hi imacsg

The image is too small.Please select biggest size for the available size of the image.

I apologise for the incovenience.I'll try to solve the problem tomorrow.

Best wishes

[imacsg]

sorry. I try to type out.


Standard ( 1) Large (2)
C S C S T
4 5 1 2 3 x 3
4 5 = 9 3 6 9 = 18

7 11 9 x7 2 3 3 x21
49 77 63 =198 42 63 63 =168

198-168 = 21 ans 168
http://www.postimage.org/image.php?v=Ts2HX4i

[tianzhu]

Hi imacsg


Where did you get the solution(image) from?

I believe you have no problem with part (a).
For part (b), use equivalent ratios to get the answer.

Best wishes

http://farm5.static.flickr.com/4081/4861176039_7b448f3afb_b.jpg\">

[imacsg]

Hi,

Thanks a lot.
The picture is from excel.

[tianzhu]

imacsg:

Hi,

Thanks a lot.
The picture is from excel.

Hi

You're welcome.

Best wishes

[Dreamybee]

Pls kindly help-Tks alot


The ratio of $2 notes to $5 notes in Joan’s piggy bank was 13:8. She exchanged 20pieces of $2 notes for some $5 notes, after which, the ratio of $2 notes to $5 notes became 4:5. What was the total value if $2 notes and $5 notes in the piggy bank at first?

[starlight1968sg]

Dreamybee:

Pls kindly help-Tks alot


The ratio of $2 notes to $5 notes in Joan's piggy bank was 13:8. She exchanged 20pieces of $2 notes for some $5 notes, after which, the ratio of $2 notes to $5 notes became 4:5. What was the total value if $2 notes and $5 notes in the piggy bank at first?

What is the ans?
I got 52 pieces of $2 and 32 pieces of $5.
So total value is $264.

[Dreamybee]

starlight1968sg:

Dreamybee:

Pls kindly help-Tks alot


The ratio of $2 notes to $5 notes in Joan's piggy bank was 13:8. She exchanged 20pieces of $2 notes for some $5 notes, after which, the ratio of $2 notes to $5 notes became 4:5. What was the total value if $2 notes and $5 notes in the piggy bank at first?

What is the ans?
I got 52 pieces of $2 and 32 pieces of $5.
So total value is $264.

Yes- ans is right but I need workings... Tks

[starlight1968sg]

Dreamybee:

Pls kindly help-Tks alot


The ratio of $2 notes to $5 notes in Joan's piggy bank was 13:8. She exchanged 20pieces of $2 notes for some $5 notes, after which, the ratio of $2 notes to $5 notes became 4:5. What was the total value if $2 notes and $5 notes in the piggy bank at first?

I don't know how to attach pic and thus I try to explain slowly.

Initial:
$2 : 13 parts
$5 : 8 parts.

20 pieces of $2 is $40 which is 8 pieces of $5.
So ratio of $2 to $5 is 20 : 8 ie 5 : 2.

I realised that at the Initial; there are 5 parts of $2 more than that of $5. And when I give 5 parts of $2 to 2 parts of $, I realised the ratio becomes 8 : 10 ie 4 : 5 (just nice as required in the question).

So 1 part is 4 pieces of notes.

There are 13 parts for $2 ie 13 * 4 = 52 pieces of $2 and
8 parts for $5 ie 8 * 4 = 32 pieces of $5.
:lol: