Thein:

hi teh_oh


i taught this method earlier itself...

but she got this problem as her homework in onsponge workbook:

Tina had some money. If she buys4 erasers she has $1 left. If she buys 8 erasers with the same amount of money she needs $3 more. How much money does Tina has and what is the cost of one eraser?

multiples of 4: 4 8 12 16 20 24
+1 : 5 9 13 17 21 25
multipes of 8: 8 16 24 32 40
-3: 5 13 21 29 37

my kid confused with the 3 matches.

Teacher also asked to erase this and to draw model.
Is it like i've to take the first match....
Thank you in advance.

Hi Thein,

When listing method is used, one has to be clear with the rationale. For eg.
multiples of 4: 4(1), 8(2), 12(3), 16(4),20(5), 24(6)
+1 : 5 9 13 17 21 25
multipes of 8: 8(1), 16(2), 24(3), 32(4), 40(5)
-3: 5 13 21 29 37

The number within bracket is the price per eraser. Although there are other matches - 13, 21 etc these actually represent different price per eraser eg. for the matching 13, looking at multiples of 4, the price per eraser is $3, whereas it is $2 per eraser looking at the multiples of 8. So the only match here is 5 which gives $1 per eraser for both multiple of 4 & 8.

Hope I didnt confuse you

cheers.

fxchow:

MathIzzzFun:

[quote=\"fxchow\"]Hi All,


Can anyone help on this question, thanks!

Mdm Zheong packed some beads into 14 small boxes and 15 big boxes.
There were equal number of beads in each small box and equal number of beads in each big box.
Each big box contained 5 more beads than each small box.
3/8 of the beads were packed in small boxes.
How many beads were there in each small box?

fxchow

Hi

Hope this helps

http://www.flickr.com/photos/62167097@N02/5664739745/in/photostream

cheers.

Hi MathIzzzFun,

Thanks for your solution.

fxchow[/quote]Hi fxchow, glad to be of help :lol:

cheers.

Hifive:

MathIzzFun:

[quote=\"Hifive\"]Hi


Need help with this question:

http://www.flickr.com/photos/62186744@N04/5679456052/in/photostream/

This is from thinkingMath@onSponge P6 book. Don't quite understand the solution provided on the back of the book. Would like to seek help if there's another method to solve this question. Thanks in advance.

Hi

Hope this helps :lol:

http://www.flickr.com/photos/62167097@N02/5679183503/in/photostream

cheers.

Hi MathIzzFun

Thank you for your help! Have a nice day![/quote]Hifive, glad to be of help :lol:

cheers.

Hifive:

Hi


Need help with this question:

http://www.flickr.com/photos/62186744@N04/5679456052/in/photostream/

This is from thinkingMath@onSponge P6 book. Don't quite understand the solution provided on the back of the book. Would like to seek help if there's another method to solve this question. Thanks in advance.

Hi

Hope this helps :lol:

http://www.flickr.com/photos/62167097@N02/5679183503/in/photostream

cheers.

cwc:

MathIzzFun:

[quote=\"cwc\"]Hi,

Need some help to solve this question. I believe I have the solution, just dunno how to use the model method to show/explain to DS. Is there a need to use model actually? Thanks & happy holiday

Question:
The ratio of the number of red counters to the number of blue counters in a box is 7 : 3. If 36 red counters are removed and 24 blue counters added, there will be an equal number of red counters and blue counters. How many red counters are there in the box?

Hi
Hope this helps :lol:

http://www.flickr.com/photos/62167097@N02/5674641247/in/photostream

cheers.

Hi,
Thanks for the help. So I see, I need to draw the model before and after, thanks.

One more question, How many red counters are there in the box? Should I be looking at the red counters before 36 was removed or after it's being removed. I found this a little vague.[/quote]Hi

You are welcome

This is an \"if\" question ie the counters are not changed at all. So, the answer is for the number of counters in the box \"initially\" ie if the counters were not changed.

cheers.

cwc:

Hi,

Need some help to solve this question. I believe I have the solution, just dunno how to use the model method to show/explain to DS. Is there a need to use model actually? Thanks & happy holiday

Question:
The ratio of the number of red counters to the number of blue counters in a box is 7 : 3. If 36 red counters are removed and 24 blue counters added, there will be an equal number of red counters and blue counters. How many red counters are there in the box?

Hi

Hope this helps :lol:

http://www.flickr.com/photos/62167097@N02/5674641247/in/photostream

cheers.

Jcong:

The number of the marbles in Box A, Box B and Box C was 195. John added 60 marbles to those in Box A, doubled the number of marbles in Box B and halved the number of marbles in Box C. The ratio of the number of marbles become 4:1:2. What is the total number of marbles in the three boxes now?

Hi

In the end, the ratio of marbles in box A, B, C -
A : B : C
= 4 : 1 : 2
= 8u : 2u : 4u >> total 14u

Initially,
A : B : C
= 8u - 60 : u : 8u

So, 8u - 60 + u + 8u = 195
17u = 255
1u = 15

14u = 14 x 15 = 210

There are 210 marbles in all the boxes now.


cheers.

Jcong:

There were 280 people at the concert. 1/4 of the males and 1/5 of the females wore glasses. Given that a total of 60 people wore glasses in the concert, how many female wore glasses?

Hi

Hope this helps

http://www.flickr.com/photos/62167097@N02/5672284885/in/photostream
cheers.

Musicstar:

Dear all,


Please help me these question. Thank you.

1) In May, the ratio of Karen's weight to Huiyu's weight was 6:5. In June , Huiyu put on 5kg and Karen lost 3kg. As a result, both of them had the same weight. What was Huiyu's weight in May?

2)The ratio of the number of Sally's stickers to the number of Willy's stickers was 4:1. After Sally bought another 13 stickers and Willy received 7 more stickers from his teacher, the ratio of Sally's stickers to Willy's stickers became 3:1 . How many stickers did Sally have at first?

3) Peter, Ali and Samy shared some marbles in the ratio of 2:4:7. They decided to play some games with their marbles in the playground. In the first game, Samy lost 8 marbles to Peter. Peter then had the same number of marbles as Ali. In the second game, Samy won some marbles from Ali but Ali lost some of his marbles in the tall grass and could not find them. The new ratio of marbles among the three boys was
Peter : Ali : Samy
2 : 1 : 3

(a) How many marbles did Peter have after the 1st game?
(b) How many more marbles does Samy have then Ali after 2nd game?

Hi

MD for Q2.

http://www.flickr.com/photos/62167097@N02/5656803790/in/photostream/

Q1.
In May,
Karen's weight : HuiYu's weight
= 6 U : 5 U

In Jun,
6U - 3 = 5U + 5
1 U = 5 + 3 = 8 kg

HuiYu's weight in May = 5U = 5 x 8 = 40kg

Q3.
Initially,
Peter : Ali : Samy
= 2u : 4u : 7u

After first game, Peter had same number of marbles as Ali after winning 8 marbles from Samy
so Peter : Ali : Samy = 4u : 4u : 5u
2u = 8 marbles ==> 1u = 4 marbles

1) After first game, Peter had 4u = 4 x 4 = 16 marbles

In the end,
Peter : Ali : Samy
= 2 : 1 : 3
= 4u : 2u : 6u (since there was no change to Peter's number of marbles, Peter still had 4u)

Samy had 4u more than Ali in the end.
4 u = 16 marbles
2) Samy had 16 marbles more than Ali

cheers.

sharmi:

Hi , Can you help me out with this P3 Problem. Appreciate if you can explain using Model. Thanks in advance.


Jeane,Agnes and Brinda has 108 Stamps. Jeane gave Agnes as many stamps as Agnes had. Agnes then gave Brinda as many stamps as Brinda had. As a result, each of them had the same number of stamps. How many stamps did Agnes receive from Jeane?

Hi

http://www.flickr.com/photos/62167097@N02/5656803746/in/photostream/

cheers.