Q&A - P4 Math

[Nebbermind]

Actually they are all some form of simultaneous equation, incl dwg models…the diff being when u substitute/replace the unknowns.


My advise to the younger ones and the not too math savvy to STAY on one method until you are proficiency in it.

Juz my 2cents

[violet04]

Hi,

Need advice of the following question:

6 pupils are standing in a circle during a Physical Education lesson. Each pupil is allowed to throw the ball to another pupil only once. What is the maximum number of throws that can be made?

1) 12
2) 13
3) 14
4) 15

The answer key said the answer is option (4). Why? :imdrowning:

[CloudeeDaz]

violet04:

Hi,

Need advice of the following question:

6 pupils are standing in a circle during a Physical Education lesson. Each pupil is allowed to throw the ball to another pupil only once. What is the maximum number of throws that can be made?

1) 12
2) 13
3) 14
4) 15

The answer key said the answer is option (4). Why? :imdrowning:

pupil 6 throws to pupil 1, 2, 3, 4, 5
pupil 1 ---------------- 2. 3, 4, 5
pupil 2 ---------------- 3, 4, 5
pupil 3 ---------------- 4, 5
pupil 4 ---------------- 5

total--------------------------------15

[snowball]

pr 4 - Fraction


1) Esther had $350 more than Kevin. Ester spent 3/4 of her money & Kevin spent 4/7 of his money. In the end, Kevin & Esther had the same amout of money left. Find the amout of money Kevin had at first.

2)At the graduation ceremony, there were 30 less boys than girls.After 3/5 of the boys & 5/8 of the girls had left the hall for recess, there was an equal number of boys & girls that remained behind. Find the number of boys who were presented at the graduation ceremony at first.

TIA

[pchong]

snowball:

pchong:

I have seen a number of posts here asking for maths solution....ur dc are still busy practicing on maths problems even after exam? I can't get mine to do any work as he said now is holiday season, suppose for him to rest and relax.

Is indeed and actually very difficult for them to do revision during the\" post exam period \" :stompfeet:

So, pchong, if your dc is already >85 in her pr 4 sa2, i think u can relax a bit bit la :please:

No, instead he scored <80 in his SA2, but I can't get him to start off with his revision...his heart is not there! Can anyone advise what can I do?

[HAPPYH]

pchong:

snowball:

[quote=\"pchong\"]I have seen a number of posts here asking for maths solution....ur dc are still busy practicing on maths problems even after exam? I can't get mine to do any work as he said now is holiday season, suppose for him to rest and relax.

Is indeed and actually very difficult for them to do revision during the\" post exam period \" :stompfeet:

So, pchong, if your dc is already >85 in her pr 4 sa2, i think u can relax a bit bit la :please:

No, instead he scored <80 in his SA2, but I can't get him to start off with his revision...his heart is not there! Can anyone advise what can I do?[/quote]Show him the KSP site. Then he will understand

I told my DD to start focusing from December second week (after our 2.5 weeks vacation). She already complians that it is too boring and not sure what to do. I simply said \"read storybooks' She gave me a look and kept quiet .

[snowball]

Nebbermind:

[

quote]
This is one book you should buy
http://edu.marshallcavendish.com/Storage/CoverImageFile/9789810195649.jpg\">

:thankyou: Nebbermind, I'll surely take a look at it :please:

[MathIzzzFun]

snowball:

pr 4 - Fraction


1) Esther had $350 more than Kevin. Ester spent 3/4 of her money & Kevin spent 4/7 of his money. In the end, Kevin & Esther had the same amout of money left. Find the amout of money Kevin had at first.

2)At the graduation ceremony, there were 30 less boys than girls.After 3/5 of the boys & 5/8 of the girls had left the hall for recess, there was an equal number of boys & girls that remained behind. Find the number of boys who were presented at the graduation ceremony at first.

TIA

equal fraction method :

1)
Esther's money left = Kevin's money left
1/4 of Esther's money = 3/7 Kevin's money
3/12 of Esther's money = 3/7 of Kevin's money
Esther's money at first --> 12 units
Kevin's money at first --> 7 units
Esther had $350 more than Kevin, so
5 units --> $ 350
1 unit --> $70
Kevin's money at first --> $490


2)
Number of boys remaining in hall = Number of girls remaining in hall
2/5 of total number of boys = 3/8 of total number of girls
6/15 of total number of boys = 6/16 of totla number of girls
Total number of boys --> 15 units
Total number of girls --> 16 units
There were 30 less boys than girls
1 unit --> 30
Total number of boys --> 450

cheers.

[snowball]

MathIzzzFun:

snowball:

pr 4 - Fraction


1) Esther had $350 more than Kevin. Ester spent 3/4 of her money & Kevin spent 4/7 of his money. In the end, Kevin & Esther had the same amout of money left. Find the amout of money Kevin had at first.

2)At the graduation ceremony, there were 30 less boys than girls.After 3/5 of the boys & 5/8 of the girls had left the hall for recess, there was an equal number of boys & girls that remained behind. Find the number of boys who were presented at the graduation ceremony at first.

TIA

equal fraction method :

1)
Esther's money left = Kevin's money left
1/4 of Esther's money = 3/7 Kevin's money
3/12 of Esther's money = 3/7 of Kevin's moneyEsther's money at first --> 12 units
Kevin's money at first --> 7 units
Esther had $350 more than Kevin, so
5 units --> $ 350
1 unit --> $70
Kevin's money at first --> $490


2)
Number of boys remaining in hall = Number of girls remaining in hall
2/5 of total number of boys = 3/8 of total number of girls
6/15 of total number of boys = 6/16 of totla number of girlsTotal number of boys --> 15 units
Total number of girls --> 16 units
There were 30 less boys than girls
1 unit --> 30
Total number of boys --> 450

cheers.

Dear MathIzzzFun, please explain ( how to explain to the kids) why we need to change to same numerator TIA

[MathIzzzFun]

snowball:

MathIzzzFun:

[quote=\"snowball\"]pr 4 - Fraction


1) Esther had $350 more than Kevin. Ester spent 3/4 of her money & Kevin spent 4/7 of his money. In the end, Kevin & Esther had the same amout of money left. Find the amout of money Kevin had at first.

2)At the graduation ceremony, there were 30 less boys than girls.After 3/5 of the boys & 5/8 of the girls had left the hall for recess, there was an equal number of boys & girls that remained behind. Find the number of boys who were presented at the graduation ceremony at first.

TIA

equal fraction method :

1)
Esther's money left = Kevin's money left
1/4 of Esther's money = 3/7 Kevin's money
3/12 of Esther's money = 3/7 of Kevin's moneyEsther's money at first --> 12 units
Kevin's money at first --> 7 units
Esther had $350 more than Kevin, so
5 units --> $ 350
1 unit --> $70
Kevin's money at first --> $490


2)
Number of boys remaining in hall = Number of girls remaining in hall
2/5 of total number of boys = 3/8 of total number of girls
6/15 of total number of boys = 6/16 of totla number of girlsTotal number of boys --> 15 units
Total number of girls --> 16 units
There were 30 less boys than girls
1 unit --> 30
Total number of boys --> 450

cheers.

Dear MathIzzzFun, please explain ( how to explain to the kids) why we need to change to same numerator TIA[/quote]so that we will get this model :

http://i48.tinypic.com/6plyj6.png\">

cheers.