Q&A - PSLE Math

[heutistmeintag]

eh, Vanilla Cake, do you give tuition? :lol:

[atrecord]

James Ang:

Cheerfuldad:

Hi all,


How do you solve the following problem:

Q. Some boys are sharing a packet of potato chips. If each boy eats 10 pieces, there will be 3 chips short. If each boy take 9 pieces, there will be 4 chips extra. How many pieces of potato chips are there in the packet?

TIA

3+4 = 7

There are 7 children

7x10-3 = 67 pieces
or
7x9+4= 67 pieces
(either way)

There are 67 pieces of potato chips in the packet

Wow, what level is this question for? I must say i've been away from school for too long...

Hi James Ang, how do you know that there are only 7 children leh?

[Poonie]

Hi James Ang


I also have a Math question. Hope you can assist.

It is a P3 question and I believe they are not allowed to use Algebra method to solve it. I can only solve it using our good old algebra method. Can you teach me how to explain to my girl using P3 methods?

X - Y = 300
X + Y = 500
What is the value of Y?

[Cheerfuldad]

atrecord:

James Ang:

[quote=\"Cheerfuldad\"]Hi all,


How do you solve the following problem:

Q. Some boys are sharing a packet of potato chips. If each boy eats 10 pieces, there will be 3 chips short. If each boy take 9 pieces, there will be 4 chips extra. How many pieces of potato chips are there in the packet?

TIA

3+4 = 7

There are 7 children

7x10-3 = 67 pieces
or
7x9+4= 67 pieces
(either way)

There are 67 pieces of potato chips in the packet

Wow, what level is this question for? I must say i've been away from school for too long...

Hi James Ang, how do you know that there are only 7 children leh?[/quote]HI atrecord,

This is a P5 question.

Same here, could you show me the step to get 7 boys.

TIA

[James Ang]

Cheerfuldad:

HI atrecord,


This is a P5 question.

Same here, could you show me the step to get 7 boys.

TIA

3 + 4 = 7 boys.

This is a logical way to solve it so simply (compares to making a list, guess and check etc). Each boy gets 1 more chip (9 pieces increase to 10 pieces) and the 4 extra pieces becomes 3 pieces short, means 4 pieces were eaten and need another 3 pieces, so total there are 4+3=7 boys since each boy eats one more piece. Most P5 children can understand this logic.

[James Ang]

Poonie:

Hi James Ang


I also have a Math question. Hope you can assist.

It is a P3 question and I believe they are not allowed to use Algebra method to solve it. I can only solve it using our good old algebra method. Can you teach me how to explain to my girl using P3 methods?

X - Y = 300
X + Y = 500
What is the value of Y?

add up both statements;

X+X -Y +Y = 300+500
X + X =800
X = 400
Y= 500-400 = 100

The value of Y is 100

[Poonie]

James Ang:

Poonie:

Hi James Ang


I also have a Math question. Hope you can assist.

It is a P3 question and I believe they are not allowed to use Algebra method to solve it. I can only solve it using our good old algebra method. Can you teach me how to explain to my girl using P3 methods?

X - Y = 300
X + Y = 500
What is the value of Y?

add up both statements;

X+X -Y +Y = 300+500
X + X =800
X = 400
Y= 500-400 = 100

The value of Y is 100

Thanks James.

[James Ang]

Poonie:

James Ang:

[quote=\"Poonie\"]Hi James Ang


I also have a Math question. Hope you can assist.

It is a P3 question and I believe they are not allowed to use Algebra method to solve it. I can only solve it using our good old algebra method. Can you teach me how to explain to my girl using P3 methods?

X - Y = 300
X + Y = 500
What is the value of Y?

add up both statements;

X+X -Y +Y = 300+500
X + X =800
X = 400
Y= 500-400 = 100

The value of Y is 100

Thanks James.[/quote]no problem.

[Cheerfuldad]

James Ang:

Cheerfuldad:

HI atrecord,


This is a P5 question.

Same here, could you show me the step to get 7 boys.

TIA

3 + 4 = 7 boys.

This is a logical way to solve it so simply (compares to making a list, guess and check etc). Each boy gets 1 more chip (9 pieces increase to 10 pieces) and the 4 extra pieces becomes 3 pieces short, means 4 pieces were eaten and need another 3 pieces, so total there are 4+3=7 boys since each boy eats one more piece. Most P5 children can understand this logic.

HI James Ang,

You have made my day! I showed your method to my child and he can understand the concept.

Thank you!

[leesf]

A & B share some beads. If A gives B 1/3 of this share, B would have 70 beads more than A. If A gives B 1/5 of his share, B would have 10 beads more than A. How many beads do A have at first?