Q&A - PSLE Math

[MathIzzzFun]

Daddy:

Hi MathIzzzfun,


Sorry to ask you some questions that I did not understand. :?

Why did the ribbons have 6 blocks instead of 3? From \"Mary bought 2/3 of ribbon\"
Why did the clips have 6 blocks also? How did you get it? Thanks..

http://i56.tinypic.com/2lwn0gw.jpg\">


Thanks.

Hi

http://i56.tinypic.com/2lwn0gw.jpg\">

Firstly, we divide the clips into 2 blocks and the ribbons into 3 blocks.. but note that the blue (representing the clips) are the same so we need to divide them into equal parts so that we can work with uniform units.. so we divide the each of the 3 blue blocks for ribbon into 2 and divide each of the two blue blocks into 3 .. so we have 6 parts in the end.

cheers.

[tianzhu]

Vanilla Cake:

Dear Uncle tianzhu,


I got the 2011 P6 Prelim Maths paper for Rosyth School but no answers were given. I had requested vlim (her son is in Rosyth School's GEP) for her http://www.kiasuparents.com/kiasu/forum/viewtopic.php?f=48&t=157&p=581820#p581820 to provide the answers. If this is not possible, could I type the answers worked out by my younger sister for you to verify them? Just to counter check and no need any worked solutions. TIA for your attention in this request.

PS: I had browsed through this Maths paper from Rosyth School and found out that it was not an easy Maths paper.

Hi VC

I’ll try my best to answer any query you may have.

But I don’t think your sister needs much help.

Judging from what I saw in Onsponge forum, barring any unforeseen circumstances, she stands a good chance of securing A/A* in PSLE Maths.

May I take this opportunity to wish her the very best.

Best wishes.

[tianzhu]

Vanilla Cake:

Dear Uncle tianzhu,


Maths Q13 (5-mark) from 2011 P6 Prelim Maths from Rosyth school mentioned about cupcakes - Vanilla (me), Chocolate (my cousin), Strawberry and Blackforest. Too bad :sick: , my flavour was the least popular.

Here's the question:

A confectionary factory baked a total of 3123 cupcakes in 4 different flavours, Strawberry, Chocolate, Vanilla and Blackforest. The Blackforest flavour was the most popular and Vanilla was the least popular flavour with a difference of 528. The difference in the number of cupcakes between Strawberry flavour and Blackforest flavour was 351. The difference in the number of cupcakes between the Chocolate-flavour and Blackforest flavour was 190.
(a) How many Blackforest-flavour cupcakes were baked?
(b) The cupcakes were packed into boxes for delivery. Each box can hold up to 20 cupcakes. What is the minimum number of boxes needed to pack all the Strawberry-flavour and Vanilla-flavour cupcakes?

PS: I hope that you and your family enjoy eating Vanilla/Chocolate/Pandan cakes.

Hi VC

Yes, I remember Chocolate Cake and David Koriadi. They must have grown up to become fine young men.

I believe you just want to check the answer.

I have the same answer as Tang and Brenda 10 (1048 and 61).

Best wishes.

[tianzhu]

Vanilla Cake:

Dear Uncle tianzhu,

Pls refer to the above picture - Henry Park Primary School 2011 P6 Prelim Maths Paper 2 Q10 - 3 marks that ck123 was talking about. Thks for your attention in this matter.

Hi VC and ck123

There are two different shades of colour in the image.

I think the student may have coloured some parts which are not included in the original question.

http://i56.tinypic.com/25uhzpy.png

Just making a guess on the shaded portion.

I am using 3.142 as pi as I don’t have my boy’s calculator with me.

Area of circle --- 3.142*36 ----- 113.11
113.11/2 ------- 56.55
56.55 - 36 ----- 20.55

Area of square -----12*12 ------144
144/2 ------72
72 – 20.55 ----- 51.45

(144 – 113.11)/4 ------ 7.72

51.45 – 7.72 ------ 43.73

Best wishes

[reddotresident]

RGPS 2011 prelim paper 1, what is the answer for Q13 pls? thank you!

[Tang]

reddotresident:

RGPS 2011 prelim paper 1, what is the answer for Q13 pls? thank you!

Hi,

The answer is (4) - 3 times.


Note: One-way traffic.

[Tang]

tianzhu:

Vanilla Cake:

Dear Uncle tianzhu,

Pls refer to the above picture - Henry Park Primary School 2011 P6 Prelim Maths Paper 2 Q10 - 3 marks that ck123 was talking about. Thks for your attention in this matter.

Hi VC and ck123

There are two different shades of colour in the image.

I think the student may have coloured some parts which are not included in the original question.

http://i56.tinypic.com/25uhzpy.png

Just making a guess on the shaded portion.

I am using 3.142 as pi as I don’t have my boy’s calculator with me.

Area of circle --- 3.142*36 ----- 113.11
113.11/2 ------- 56.55
56.55 - 36 ----- 20.55

Area of square -----12*12 ------144
144/2 ------72
72 – 20.55 ----- 51.45

(144 – 113.11)/4 ------ 7.72

51.45 – 7.72 ------ 43.73

Best wishes

Hi,

Both parts are shaded.

The area of the smaller part is: (36 - 6 pi) cm2.

[Brenda10]

tianzhu:

I have the same answer as Tang and Brenda 10 (1048 and 61).


Best wishes.

Hi Tianzhu/Tang

Thank you for the your confirmation of the answer to this Rosyth 2011 Prelim P2 Q13.

[Belle2011]

Eddow:

http://i51.tinypic.com/x1n6zl.png\">

Answer given: (b) ~83.91 cm

Pls wait for Uncle tianzhu / MathIzzzFun to provide worked solutions.
Thks.

Thanks Tianzhu for the solution. Maybe this might be easier, as I coundn't figure out the rotation myself... :?

Given the 135 degree, angle ODB = 45 degree.
If you draw a line joining OT, angle OTE = 45 degree (half of 90 degree of square) . This straight away give OT = DB.
And the rest of the calculation applies..[/quote]
I don't understand why OT = DB as T is a region and not a point.
Thank-you.

[Andrew Lee]

youngtay:

ck123:

Hi youngtay


Answer is 17/8.

eg. May has $2 and Jane has $3.
Question : What fraction of Jane's money is May's?
Answer : 2/3
Question : What is the fraction of Jane's $ to May's?
Answer : 3/2
so just need to remember after the word is is what you want.

Hope is help..

ck123

Thanks for your help.

Hi, can help me?

http://i56.tinypic.com/kagzv9.jpg\">