Q&A - PSLE Math

[Mr OK]

Hello everyone, I’m new to this forum. Would appreciate some help for these questions:-


1) Mr Lau sells notebooks at $2 each and files at $3 each. After he sold 100 notebooks and files, the amount he collected from the sale of notebooks was $60 more than than the amount collected from the sale of files. How many notebooks did Mr Lau sell?

2) There are some blue chips and red chips in a bag. If 2 blue chips are removed from the bag, the number of blue chips will be 1/6 of the total number of chips left.
If 4 red chips are removed from the bag, the number of blue chips will be 1/4 of the total number of chips left. How many chips are there in the bag?

3) Sally had 20 more books than Ali. After Sally gave 15 of her books to Ali, Sally’s remaining number of books was 3/8 of their total number of books.
A) How many books did Ali have at first?
B) What is the difference in the number of books they finally had?

[tianzhu]

Chan09:

Need some help on this:

A has $900 more than B. A gave B some money. In the end B had $800 more than A. How much did A give B?
Tried model diagram but difficult to visualise? Tks

Hi

This question looks easy at first glance as it contains not too much information.However,it might be tricky.

A gave B 850.

Picture A with 1900 and B with 1000 at first.

The amount of money before and after stayed the same. Perhaps this might help you to draw the MD.

Best wishes

[tianzhu]

homeworkmummy:

Hi, can someone help me with St Nicks 2011 P6 SA1 paper Q26. Can't upload the document as I don't have a scanner.....appreciate it.

Hi

Q26 on page 13

http://www.orlesson.org/orp/11Ma/2011-P6-Math-SA1-StNics.pdf

X,Y and Z shared the shaded part.

Z (shaded) -------- 3
Z (unshaded) -------- 5

X (shaded) -------- 3
X (unshaded) -------- 9

Y (shaded) -------- 3
Y (unshaded) -------- 12

Shaded area of Y : total area of figure ------- 3:29 (3+5+9+12)

Best wishes

[homeworkmummy]

tianzhu:

homeworkmummy:

Hi, can someone help me with St Nicks 2011 P6 SA1 paper Q26. Can't upload the document as I don't have a scanner.....appreciate it.

Hi

Q26 on page 13

http://www.orlesson.org/orp/11Ma/2011-P6-Math-SA1-StNics.pdf

X,Y and Z shared the shaded part.

Z (shaded) -------- 3
Z (unshaded) -------- 5

X (shaded) -------- 3
X (unshaded) -------- 9

Y (shaded) -------- 3
Y (unshaded) -------- 12

Shaded area of Y : total area of figure ------- 3:29 (3+5+9+12)

Best wishes

Thanks Tianzhu for the help!

[kklau]

Hi,

Appreciate anyone's help for this question.

The diagram, not drawn to scale, shows two similar triangles and quadrants. Find the area of the shaded part.

http://i48.tinypic.com/9vi2ir.jpg\">

Thank you!

[MathIzzzFun]

Mr OK:

Hello everyone, I'm new to this forum. Would appreciate some help for these questions:-


1) Mr Lau sells notebooks at $2 each and files at $3 each. After he sold 100 notebooks and files, the amount he collected from the sale of notebooks was $60 more than than the amount collected from the sale of files. How many notebooks did Mr Lau sell?

Hi

supposition or assumptive method, using area model...

http://i46.tinypic.com/n4bf5s.png\">

cheers.

[MathIzzzFun]

kklau:

Hi,

Appreciate anyone's help for this question.

The diagram, not drawn to scale, shows two similar triangles and quadrants. Find the area of the shaded part.

http://i48.tinypic.com/9vi2ir.jpg\">

Thank you!

Hi

http://i47.tinypic.com/2u77kwn.png\">

cheers.

[tianzhu]

kklau:

Hi,

Appreciate anyone's help for this question.

The diagram, not drawn to scale, shows two similar triangles and quadrants. Find the area of the shaded part.

http://i48.tinypic.com/9vi2ir.jpg\">

Thank you!

Hi

P6 students will be well versed in finding out the area of square when its diagonal is given.

Shaded area -------- Area of semi circle of radius 10 cm - area of square with diagonal 10cm

Shaded area -------- (3.14*100)/2 – (10*10)/2 --------- 157 – 50 ------ 107

Best wishes

[MathIzzzFun]

Mr OK:

Hello everyone, I'm new to this forum. Would appreciate some help for these questions:-


2) There are some blue chips and red chips in a bag. If 2 blue chips are removed from the bag, the number of blue chips will be 1/6 of the total number of chips left.
If 4 red chips are removed from the bag, the number of blue chips will be 1/4 of the total number of chips left. How many chips are there in the bag?

Hi

using MD..

http://i49.tinypic.com/14w8ytt.png\">

cheers.

[MathIzzzFun]

Mr OK:

Hello everyone, I'm new to this forum. Would appreciate some help for these questions:-


3) Sally had 20 more books than Ali. After Sally gave 15 of her books to Ali, Sally's remaining number of books was 3/8 of their total number of books.
A) How many books did Ali have at first?
B) What is the difference in the number of books they finally had?

Hi

http://i48.tinypic.com/2mnq3nk.png\">

cheers.