Q&A - PSLE Math

[tianzhu]

Daddy:

I do not understand that the model for chicken is not the same as duck and quail. Which part of the statement told that they are different? Please help!!

Hi

The boxes showing chicken eggs are different from those of ducks and quails because they belong to different sets of objects.

Best wishes

[Daddy]

Hi Tianzhu,


I still not understand.
Is it the chicken’s egg did not do a compare, Stand alone model?
Duck eggs compared with quail eggs, so their model units are the same.
Am I corrected?

Thanks

[Daddy]

Hi Tiazhu,

Is my answer corrected?

Jim and his sister shared some money. 1/3 of Jim's amount is 3/4 of his sister's share. If the difference in their share of money was $50, how much money did Jim have?

Jim [][][][][][][][][]
sister [][][][][][][][][][][][]
|------> $50
3u -> $50
1u -> 50/3
Jim -> 9u
= 9 x 50/3
= $150

[meremortal]

Daddy:

Hi Tianzhu,


I still not understand.
Is it the chicken's egg did not do a compare, Stand alone model?
Duck eggs compared with quail eggs, so their model units are the same.
Am I corrected?

Thanks

What was the question?

[tianzhu]

Daddy:

Hi Tianzhu,


I still not understand.
Is it the chicken's egg did not do a compare, Stand alone model?
Duck eggs compared with quail eggs, so their model units are the same.
Am I corrected?

Thanks

Hi

Take for example, John is three times as old as his son.
In MD, we draw 3 boxes for John and 1 box for his son.

In this question, there is a link or relationship between duck and quail eggs,. He sold 3 times as many quail eggs as duck eggs.
So, if duck eggs are represented by 2 boxes, then quail eggs are represented by 6 boxes.

The chicken eggs are of different sets of objects; hence the units are of different kind and measure.

Best wishes

[Daddy]

Hi meremortal,


http://i52.tinypic.com/1058s5x.jpg\">

Thanks

[Daddy]

:thankyou: Tianzhu..

[tianzhu]

Daddy:

Hi Tiazhu,

Is my answer corrected?

Jim and his sister shared some money. 1/3 of Jim's amount is 3/4 of his sister's share. If the difference in their share of money was $50, how much money did Jim have?

Jim [][][][][][][][][]
sister [][][][][][][][][][][][]
|------> $50
3u -> $50
1u -> 50/3
Jim -> 9u
= 9 x 50/3
= $150

Hi

1/3 of Jim’s share is equal to of 3/4 his sister.

This means Jim has a total of 9 units and his sister has a total of 4 units

Difference ----- 9 - 4 -------5

5 units -------50
1 unit ------10

Jim ------9 units -------90

Best wishes.

[tianzhu]

Daddy:

:thankyou: Tianzhu..

Hi

You're welcome.

Wishing you the very best for PSLE 2011.

Best wishes

[meremortal]

tianzhu:

Daddy:

Hi Tianzhu,


I still not understand.
Is it the chicken's egg did not do a compare, Stand alone model?
Duck eggs compared with quail eggs, so their model units are the same.
Am I corrected?

Thanks

In this question, there is a link or relationship between duck and quail eggs,. He sold 3 times as many quail eggs as duck eggs.
So, if duck eggs are represented by 2 boxes, then quail eggs are represented by 6 boxes.

The chicken eggs are of different sets of objects; hence the units are of different kind and measure.

Best wishes

To solve out the number of chickens originally, can we resort to algebra?

So from the models we can solve for the Quail and Ducks, and simple deduction will give us the number of Chicken eggs remaining: 205 (all eggs) - 45 (duck) - 90 (Quail) = 70 (Chicken eggs remaining)

So now we know 70 is 40% of all chicken eggs originally. Therefore, 70/0.4 = 175.

Is this allowed in P5/P6?