Q&A - PSLE Math

[tianzhu]

rossypolly:

hi there! Pls help me with this qn


Sam bought some vanilla cookies and gave 1/2 of them to Mike.
Mike bought some chocholate bars and gave 1/2 of them to Sam.
Sam ate 8 chocolate bars and Mike ate 16 vanilla cookies.
The ratio of Sam's vanilla cookies to chocolate bars became 8:1 and the ratio of Mike's vanilla cookies to chocolate bars became 3:1.

How many vanilla cookies did Sam buy?

(Really appreciate your help)

Hi rossypolly

Good Morning

This question is pretty similar to Q18 of PSLE Maths 2009.It has been discussed previously in this forum.

Due to time constraints, I’d not draw the MD this time, hope the following pointers would help you to draw the MD yourself.

After Sam had eaten 8 chocolates
Vanilla ----- 8 units
Chocolate -----1 unit

After Mike had eaten 16 vanilla cookies
Vanilla ----- 3 parts
Chocolate ----- 1 part
1 part ------ 1 unit+8

Now, compare, the MD for vanilla cookies

3 units + 24 + 16 -------8 units
5 units ----- 40
1 unit ------8
8 units ----- 64

Sam had 128 vanilla cookies.

If you need the MD, please let me know. I’ll draw it at a later time if there is no MD solution from others.

Best wishes

[small]

tianzhu:

small:

Please help and TIA..


Question: For every tree that Imran plants, he is paid $4. A bonus of 20 is given to him for every 25 trees he plants within the same day. On the average, how trees must Imran plant a day if he wishes to earn a total of $760 over a period of 5 days?

.

Hi small

Good Morning

760/5 --- 152

For 25 trees, he earned (100+20) ----- 120

152 ----- 120+32

32/4 ----- 8

Number of trees ------ 25+8 ------33

Best wishes

Good morning Tianzhu,

Thanks very much... :celebrate:

No wonder I got the wrong answer. Wrong step always give me the wrong answer.
I did not divide the total money with 5 days first, instead I divided $750 with $120.


.

[tianzhu]

small:

Good morning Tianzhu,

Thanks very much... :celebrate:

No wonder I got the wrong answer. Wrong step always give me the wrong answer.
I did not divide the total money with 5 days first, instead I divided $750 with $120.

Hi

You're welcome.

Best wishes

[hashroop]

Dear friends

What is the simplest way to answer questions on nets formation? The question will usually be an ‘unfolded’ diagram of a certain solid and would ask which solid will be formed by the net. Is there a shortcut to it or we literally have to fold papers? (lol)

[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?

[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.

[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\">

[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.