Q&A - PSLE Math

[tianzhu]

Happy Mama:

Hi, can someone please help me solve this? Manyt thanks in advance.


Mary has 260 blue and green marbles. She gave 50% of blue and 20% of green marbles away, and has left 150 marbles. How many blue marbles doe she have at first?

Hi Happy Mama

Please confirm the numbers in your question.

Best wishes

[Happy Mama]

tianzhu:

Happy Mama:

Hi, can someone please help me solve this? Manyt thanks in advance.


Mary has 260 blue and green marbles. She gave 50% of blue and 20% of green marbles away, and has left 150 marbles. How many blue marbles doe she have at first?

Hi Happy Mama

Please confirm the numbers in your question.

Best wishes

Hi Tianzhu, the numbers are correct. We are also wondering why as we have tried and even tried backwards and it didn't work. Thanks so much.

[Belle2011]

tianzhu:

Belle2011:

Dear all,

Please help to solve:

A, B and C shared a tin of cookies. A took 5/6 of the tin of cookies and 1/3 of a cookie. B took 5/6 of the remaining tin of cookies and 1/3 of a cookie. C received only 2 cookies. How many more cookies did A have than B?
Thank-you.

Cheers,
Belle.

Hi Belle2011

This question looks familiar, it's been discussed before.

Hope this helps.

Best wishes.

http://farm5.static.flickr.com/4019/4713599224_8f586290c0_b.jpg\">

Dear tian-zhu,
Thank-you for your prompt attention. The part on1 unit is 21/3 is a bit tough to understand.
Anyway, thank-you.
Cheers,
Belle.

[tianzhu]

Belle2011:

Dear tian-zhu,

Thank-you for your prompt attention. The part on1 unit is 21/3 is a bit tough to understand.
Anyway, thank-you.
Cheers,
Belle.

Hi

After B took 5/6 of the remaining tin of cookies, 1/6 of the tin was left.

This 1/6 of tin comprises of 1/3 of a cookie and the remaining 2 cookies, therefore 1 unit equals 2 1/3.

Best wishes

[Emelyn]

Hi,


Need some urgent help here.

Qn : Jan and Kay had equal number of sweets and equal number of chocolates. Jan ate 12 sweets and Kay ate 18 chocolates and then the ratio of Jan’s sweets to chocolates became 1:7, and the ration of Kay’s sweets to chocolates became 1:4. How many sweets did Jan have at first ?

MTIA !!

[tianzhu]

Happy Mama:

Hi Tianzhu, the numbers are correct. We are also wondering why as we have tried and even tried backwards and it didn't work. Thanks so much.

Hi Happy Mama

Based on the original question, you’ll get the answer in decimals.

If you change 20% to 30%, you’ll get a nice numbers for the answer.

Best wishes

[tianzhu]

Emelyn:

Hi,


Need some urgent help here.

Qn : Jan and Kay had equal number of sweets and equal number of chocolates. Jan ate 12 sweets and Kay ate 18 chocolates and then the ratio of Jan's sweets to chocolates became 1:7, and the ration of Kay's sweets to chocolates became 1:4. How many sweets did Jan have at first ?

MTIA !!

Hi Emelyn

This question has been discussed earlier.

This question is a modified version of a question from PSLE 2009.

You may use MD or Units Method to solve it.

Once you get the MD done, all you need to do is to compare the number of chocolates of Jan and Kay.

Hope this helps.

Best wishes.

http://farm6.static.flickr.com/5133/5473929452_1688f4c2ee_b.jpg\">

[Happy Mama]

tianzhu:

Happy Mama:

Hi Tianzhu, the numbers are correct. We are also wondering why as we have tried and even tried backwards and it didn't work. Thanks so much.

Hi Happy Mama

Based on the original question, you’ll get the answer in decimals.

If you change 20% to 30%, you’ll get a nice numbers for the answer.

Best wishes

Oh ok. Thank you very much, Tianzhu.

[tianzhu]

Happy Mama:

Oh ok. Thank you very much, Tianzhu.

Hi Happy Mama

You're welcome.

Best wishes

[Emelyn]

tianzhu:

Emelyn:

Hi,


Need some urgent help here.

Qn : Jan and Kay had equal number of sweets and equal number of chocolates. Jan ate 12 sweets and Kay ate 18 chocolates and then the ratio of Jan's sweets to chocolates became 1:7, and the ration of Kay's sweets to chocolates became 1:4. How many sweets did Jan have at first ?

MTIA !!

Hi Emelyn

This question has been discussed earlier.

This question is a modified version of a question from PSLE 2009.

You may use MD or Units Method to solve it.

Once you get the MD done, all you need to do is to compare the number of chocolates of Jan and Kay.

Hope this helps.

Best wishes.

Oopss... sorry.... for not checking the earlier discussion.
Thanks for explaining it again.