Q&A - PSLE Math

[tianzhu]

Hi tiger262


Yes, a thread on secondary school Maths does exist, please follow this link.
http://www.kiasuparents.com/kiasu/forum/viewtopic.php?t=8315&start=0

It is not as active as the primary section; maybe secondary students are more independent.

Best wishes

[tiger262]

tianzhu:

Hi tiger262


Yes, a thread on secondary school Maths does exist, please follow this link.
http://www.kiasuparents.com/kiasu/forum/viewtopic.php?t=8315&start=0

It is not as active as the primary section; maybe secondary students are more independent.

Best wishes

Thank you very much for the prompt reply, Mr. Tianzhu. You are right in saying that the thread may not be as active as the PSLE thread, since Secondary students are more independent.

In my view, one more reason could be that parents are not that closely involved with Sec-1 studies when compared to their involvement in the PSLE stage, although I wonder why.

Thanks and Regards.

[Muffins]

I guess it's because they are worried about which school their child would go to, and in Sec 1, when they are alrea in their school, it's not as important...

[SLeng]

Hi Vanilla Cake and Parents,


Any clues where can I find past years PSLE exam questions for English, Maths, Science and Chinese ?

[tianzhu]

SLeng:

Hi Vanilla Cake and Parents,


Any clues where can I find past years PSLE exam questions for English, Maths, Science and Chinese ?

Hi

You can buy the books from Popular Bookstore.
http://www.seab.gov.sg/psle/pslePublications.html

Best wishes

[SLeng]

Hi Tianzhu,


Thanks

[tianzhu]

SLeng:

Hi Tianzhu,


Thanks

Hi

You're welcome.

Best wishes

[oovi-yah]

pls help me on these 3 questions


1.Ali,bala ,clyde and dingyi shared a box of pens.ali received 20% of the total number of pens which bala ,clyde and dingyireceived altogether .bala received 50% of the total number of pens which ali,clyde and dingyi received altogether.clyde received 80% of the total number of pens which ali,bala and dingyi received altogether.dingyi received 6 pens.how many pens were in the box at first?

2.jolene and penny had a sun of money.jolene gave penny 0.4 of her money .penny then gave jolene 1/2 of her money.in the end jolene had three times the amount of money that penny had.if jolene gave penny $125 more than what penny gave jolene,how much money did jolene have at first?

3.Mrs.raju bought 20 bottles of milk and 5 boxes of cornflakes from supermarket.if she had bought these items at 20% discount,the amount of money she saved could buy another 3 more boxes of cornflakes at the usual price.the usual price of a bottle of milk was 2.15.what was the usual price of a box of cornflakes?

[starlight1968sg]

oovi-yah:

pls help me on these 3 questions


1.Ali,bala ,clyde and dingyi shared a box of pens.ali received 20% of the total number of pens which bala ,clyde and dingyireceived altogether .bala received 50% of the total number of pens which ali,clyde and dingyi received altogether.clyde received 80% of the total number of pens which ali,bala and dingyi received altogether.dingyi received 6 pens.how many pens were in the box at first?

2.jolene and penny had a sun of money.jolene gave penny 0.4 of her money .penny then gave jolene 1/2 of her money.in the end jolene had three times the amount of money that penny had.if jolene gave penny $125 more than what penny gave jolene,how much money did jolene have at first?

3.Mrs.raju bought 20 bottles of milk and 5 boxes of cornflakes from supermarket.if she had bought these items at 20% discount,the amount of money she saved could buy another 3 more boxes of cornflakes at the usual price.the usual price of a bottle of milk was 2.15.what was the usual price of a box of cornflakes?

1) A: B+C+D = 20:100 = 1:5
B: A+C+D = 50:100 = 1:2
A+B+D = 80:100 = 4:5

Since the total number of pens involved is the same for the above 3 cases, find the LCM of 6,3,9 which is 18.

Thus the ratios become
A:B+C+D = 3:15
B:A+C+D = 6:12
C:A+B+D = 8:10

A:B:C: D = 3:6:8: ONE to make up the total of 18.
Thus D has 1 part which is 6 pens.
Total parts = 18 and thus 18*6 = 108 pens.

2) Draw models:
J has 10 units, Penny has 1 part.
J gave 4 u to Penny.
Thus Penny has 1 p + 4u.
Then Penny gave J half of what she has ie 1/2 P + 2u.
After that J has thrice as what Penny has.
So, 6u = 2 (1/2P +2u) = P+4u
P=2u.

J gave 4u to Penny.
Penny gave 1/2P + 2u = 3u to J.
Their difference is 1u which corresponds to $125.

J has 10u = $1250.

[iFruit]

oovi-yah:

pls help me on these 3 questions


3.Mrs.raju bought 20 bottles of milk and 5 boxes of cornflakes from supermarket.if she had bought these items at 20% discount,the amount of money she saved could buy another 3 more boxes of cornflakes at the usual price.the usual price of a bottle of milk was 2.15.what was the usual price of a box of cornflakes?

20% of 20 bottles of milk = 1/5 x 20 x2.15 = 8.6

Let price of a box of cornflakes = u

20% of 5 boxes of cornflakes = 1/5 x 5 x u = u

8.6 +u = 3u ----> 2u = 8.6 ---> u = 4.3

Usual price of a box of cornflakes = $4.30