Q&A - PSLE Math

[fightingmom]

Hi,


Can someone help with the following question:

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TIA !

[tianzhu]

fightingmom:

Hi,


Can someone help with the following question:

http://i47.tinypic.com/c2lxx.jpg\">

TIA !

Hi

This question has been discussed earlier.

Best wishes

http://farm5.staticflickr.com/4133/4975546078_eaed16dcca_z.jpg\">

[fightingmom]

tianzhu:

fightingmom:

Hi,


Can someone help with the following question:

http://i47.tinypic.com/c2lxx.jpg\">

TIA !

Hi

This question has been discussed earlier.

Best wishes

http://farm5.staticflickr.com/4133/4975546078_eaed16dcca_z.jpg\">

:thankyou: tianzhu for your prompt reply !

[peggy]

Please assist with this.


There are more pupils in school A than school B. 30%of the pupils in school A is 45 more than 40% the pupils in school B. If 10% of the pupils in school A leaves to join school B, there will be 200 more pupils in school A than in school B.
a. How many pupils are there in school B?
B. How many percent less pupils are there in school B than school A?
Leave your answer as a fraction in the simplest form.

Thanks!

[tianzhu]

peggy:

Please assist with this.


There are more pupils in school A than school B. 30%of the pupils in school A is 45 more than 40% the pupils in school B. If 10% of the pupils in school A leaves to join school B, there will be 200 more pupils in school A than in school B.
a. How many pupils are there in school B?
B. How many percent less pupils are there in school B than school A?
Leave your answer as a fraction in the simplest form.

Thanks!

Hi

You may work with MD or units.

One possible way.

30% ------- 3/10 ------- 6/20

40% ------- 2/5 -------- 6/15

A common multiple of 2 and 3 is 6.

30% of the pupils in school A is 45 more than 40% the pupils in school B.

6 units ------- 6 units + 45

2 units -------- 2 units + 15

At first

School A ------- 20 units + 150

School B ------- 15 units

If 10% of the pupils in school A leaves to join school B, there will be 200 more pupils in school A than in school B.

In the end

School A ------- 18 units + 135

School B ------- 17 units + 15

18 units + 135 ------- 17 units + 15 + 200

1 unit ------- 80

Number of pupils@B ------- 15*80 ------- 1200

Number of pupils@A -------- 20*80 + 150 --------- 1750

1750 – 1200 -------- 550

550/1750*100% ------- 31 3/7%

Best wishes

[peggy]

Thanks, Tianzhu!

[kwcllf]

An Express train travels from Town A to Town B. A Normal train travels from Town B to Town A at the same time. When the two trains meet, the Express train has travelled 105km more than the Normal train. The two trains reached their destination in 6 hours and 10 hours respectively. What is the distance between the two towns?


Thanks.

[tianzhu]

kwcllf:

An Express train travels from Town A to Town B. A Normal train travels from Town B to Town A at the same time. When the two trains meet, the Express train has travelled 105km more than the Normal train. The two trains reached their destination in 6 hours and 10 hours respectively. What is the distance between the two towns?


Thanks.

Hi

For Speed questions, it’s useful to begin with a simple diagram.

A neat way is to use inverse proportion.

Time taken by express train: Time taken by normal train -------- 6:10 ------- 3:5

Distance covered by express train: Distance covered by normal train ------- 5:3

5-3 ------- 2

2 units ------- 105

1 unit ------- 52.5

Distance between two towns -------- 8*52.5 -------- 420 km

Best wishes

[kwcllf]

tianzhu:

kwcllf:

An Express train travels from Town A to Town B. A Normal train travels from Town B to Town A at the same time. When the two trains meet, the Express train has travelled 105km more than the Normal train. The two trains reached their destination in 6 hours and 10 hours respectively. What is the distance between the two towns?


Thanks.

Hi

For Speed questions, it’s useful to begin with a simple diagram.

A neat way is to use inverse proportion.

Time taken by express train: Time taken by normal train -------- 6:10 ------- 3:5

Distance covered by express train: Distance covered by normal train ------- 5:3

5-3 ------- 2

2 units ------- 105

1 unit ------- 52.5

Distance between two towns -------- 8*52.5 -------- 420 km

Best wishes

Thanks Tianzhu!

[zeemimi]

Can i find out if the child will be penalised for using algebra to solve Math questions?