## Q&A - PSLE Math

### Re: Q&A - PSLE Math

Hi pls help on the below

There are 8 more adults in swimming class A than swimming class B . If 8 men leave swimming class A, 1/3 of the adults

In swimming class A will be men . If 10 women leave swimming class B , the ratio of men to women in swimming class B

Will become 2:3 . Given that the ratio of the total number of men to women in both swimming

Classes is 3:5, how many adults are there in swimming class A ?

Thanks very much !

Fly2high

There are 8 more adults in swimming class A than swimming class B . If 8 men leave swimming class A, 1/3 of the adults

In swimming class A will be men . If 10 women leave swimming class B , the ratio of men to women in swimming class B

Will become 2:3 . Given that the ratio of the total number of men to women in both swimming

Classes is 3:5, how many adults are there in swimming class A ?

Thanks very much !

Fly2high

- alfretztay
- KiasuGrandMaster
**Posts:**1199**Joined:**Sun Sep 12,**Total Likes:**5

### Re: Q&A - PSLE Math

I would solve the above question as follows :Fly2high wrote:Hi pls help on the below

There are 8 more adults in swimming class A than swimming class B . If 8 men leave swimming class A, 1/3 of the adults

In swimming class A will be men . If 10 women leave swimming class B , the ratio of men to women in swimming class B

Will become 2:3 . Given that the ratio of the total number of men to women in both swimming

Classes is 3:5, how many adults are there in swimming class A ?

Thanks very much !

Fly2high

For class A,

men : women

1u + 8 : 2u

For class B,

men : women

2p : 3p + 10

1u + 8 + 2u – (2p + 3p + 10) = 8

3u ——- 5p + 10

[(1u + 8) + 2p] x 5 = [2u + (3p + 10)] x 3

5u + 40 + 10p = 6u + 9p + 30

1u ——- 10 + 1p

3(10 + 1p) ——- 5p + 10

2p ——- 20

1p ——- 20/2 = 10

1u ——- 10 + 10 = 20

1u + 8 + 2u ——- 3 x 20 + 8 = 68

Ans : 68 adults.

### Re: Q&A - PSLE Math

thanksEnder wrote:vvv

A: 1702339

Subject: Math

Level: P6

Tags: Ratio, Fraction, u

Source:

^^^

Let male be 5u and female be 3u at noon

After 10 minutes, 1/5 of male (1u) and 1/2 of female(1.5u) left

male =4u

female = 1.5u

Total number of people during the 10 minutes after noon.

Total = 121 + 23 + 32 = 176

4u + 1.5u =176

u= 32

Total people at noon time = 5u + 3u = 8u = 256#

### Q&A - PSLE Math

please help :

1) The ratio of the number of marbles May, Teddy and Sam had was 3:5:2. During a game, May lost half of her marbles to Teddy. Teddy lost 20 marbles to Sam who then had 3 times the number of marbles May had at the end of the game.

a) What was the percentage increase in the number of marbles Sam had at the end of the game?

b) How many marbles did Teddy have at the end of the game?

2) At a fun-raising event, 60% of the people were male and the rest were female. 20% of the female left the event in the afternoon.

In the evening, after 33 male and 35 female left the event, 75% of the people at the event were male.

a) What percentage of the people left the event in the afternoon?

b) How many people were there at the start of the fun raising event?

1) The ratio of the number of marbles May, Teddy and Sam had was 3:5:2. During a game, May lost half of her marbles to Teddy. Teddy lost 20 marbles to Sam who then had 3 times the number of marbles May had at the end of the game.

a) What was the percentage increase in the number of marbles Sam had at the end of the game?

b) How many marbles did Teddy have at the end of the game?

2) At a fun-raising event, 60% of the people were male and the rest were female. 20% of the female left the event in the afternoon.

In the evening, after 33 male and 35 female left the event, 75% of the people at the event were male.

a) What percentage of the people left the event in the afternoon?

b) How many people were there at the start of the fun raising event?

- ChiefKiasu
- Site Admin
**Posts:**17898**Joined:**Mon Sep 03,**Location:**Singapore**Total Likes:**497

### Re: Q&A - PSLE Math

When posting questions, please post only 1 question per post, and not multiple in 1 post. It makes it easier to get answers for your questions.

### Re: Q&A - PSLE Math

vvv

A: 1702574

Subject: Math

Level: P6

Tags: Ratio, Percentage, u

Source:

^^^

Question 1

M :T : S => 3u : 5u : 2u

After the game

M : T : S => 1.5u : 6.5u-20 : 2u + 20

We know in the end Sam is 3 times of May

2u + 20 = 3X(1.5u)

2u + 20 = 4.5u

2.5u = 20

u = 8

a) before the game Sam =2u = 16

After the game, he gain 20 marbles from Teddy

Percentage increase = 20/16 X100 = 125% ##

b) in the end Teddy has 6.5u-20 = 32 marbles ##

Question 2,

Please see the link. Already answered,

http://www.kiasuparents.com/kiasu/forum ... 6#p1682926

A: 1702574

Subject: Math

Level: P6

Tags: Ratio, Percentage, u

Source:

^^^

Question 1

M :T : S => 3u : 5u : 2u

After the game

M : T : S => 1.5u : 6.5u-20 : 2u + 20

We know in the end Sam is 3 times of May

2u + 20 = 3X(1.5u)

2u + 20 = 4.5u

2.5u = 20

u = 8

a) before the game Sam =2u = 16

After the game, he gain 20 marbles from Teddy

Percentage increase = 20/16 X100 = 125% ##

b) in the end Teddy has 6.5u-20 = 32 marbles ##

Question 2,

Please see the link. Already answered,

http://www.kiasuparents.com/kiasu/forum ... 6#p1682926

### Re: Q&A - PSLE Math

ozora wrote:Need some guide on the following questions

Thanks

The question says:Ender wrote:vvv

A: 1702339

Subject: Math

Level: P6

Tags: Ratio, Fraction, u

Source:

^^^

Let male be 5u and female be 3u at noon

After 10 minutes, 1/5 of male (1u) and 1/2 of female(1.5u) left

male =4u

female = 1.5u

Total number of people during the 10 minutes after noon.

Total = 121 + 23 + 32 = 176

4u + 1.5u =176

u= 32

Total people at noon time = 5u + 3u = 8u = 256#

"Ten minutes later, 1/5 of the males and 1/2 of the females

**LEFT**the bus terminal.

Twenty minutes later, when another 23 males and 32 females

**CAME**to the bus terminal, there were a total of 121 people..."

I believe at 12:10, there should be

Total = 121 - 23 - 32 = 66

4u + 1.5u = 66

1u = 12

Total people at noon time = 5u + 3u = 8u =

**96**

### Re: Q&A - PSLE Math

Right, Thanks. I misread the the question. The answer as above by Bigdevil.BigDevil wrote:ozora wrote:Need some guide on the following questions

ThanksThe question says:Ender wrote:vvv

A: 1702339

Subject: Math

Level: P6

Tags: Ratio, Fraction, u

Source:

^^^

Let male be 5u and female be 3u at noon

After 10 minutes, 1/5 of male (1u) and 1/2 of female(1.5u) left

male =4u

female = 1.5u

Total number of people during the 10 minutes after noon.

Total = 121 + 23 + 32 = 176

4u + 1.5u =176

u= 32

Total people at noon time = 5u + 3u = 8u = 256#

"Ten minutes later, 1/5 of the males and 1/2 of the femalesLEFTthe bus terminal.

Twenty minutes later, when another 23 males and 32 femalesCAMEto the bus terminal, there were a total of 121 people..."

I believe at 12:10, there should be

Total = 121 - 23 - 32 = 66

4u + 1.5u = 66

1u = 12

Total people at noon time = 5u + 3u = 8u =96

- alfretztay
- KiasuGrandMaster
**Posts:**1199**Joined:**Sun Sep 12,**Total Likes:**5