## Q&A - PSLE Math

Academic support for Primary 6 and PSLE
speedmaths.com
BrownBelt
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### Re: Q&A - PSLE Math

Ice watch wrote:

The question asked for "this year", and NOT "last year."

Cheers

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RJ_164
KiasuNewbie
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### Re: Q&A - PSLE Math

Jared packed some sweets and chocolates into gift bags as door gifts for his birthday party. He tried
putting every 2 sweets with 1 chocolate into a bag and found that he had 30 chocolate left. When he put every 2 sweets with 2 chocolates, he needed another 50 chocolates. How many sweets and chocolates did he have altogether?

nicnac
KiasuGrandMaster
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### Re: Q&A - PSLE Math

Jared packed some sweets and chocolates into gift bags as door gifts for his birthday party. He tried
putting every 2 sweets with 1 chocolate into a bag and found that he had 30 chocolate left. When he put every 2 sweets with 2 chocolates, he needed another 50 chocolates. How many sweets and chocolates did he have altogether?
To put one more chocolates in each bag, he will need 80 chocolates. So he has a total of 80 gift bags.
Total chocolates and candies he had 270 (3*80 + 30).

dido
OrangeBelt
Posts: 64
Joined: Sun Jul 05,

### Re: Q&A - PSLE Math

Hi,

I am trying to help my P6 child in his Math revision, but I couldn't solve. Can someone help? Thanks a million.

God Bless

EconsPhDTutor
OrangeBelt
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### Re: Q&A - PSLE Math

dido wrote:Hi,

I am trying to help my P6 child in his Math revision, but I couldn't solve. Can someone help? Thanks a million.

God Bless

15(a) 14 cm × 756.25 cm² =10,587.5 cm³.

15(b) Let X be the water level of Tank B after all the pouring is done.

Then (X - 20) cm is the increase in the water level of Tank B and (28 - X) cm is the decrease in the water level of Tank A.

If the water level in Tank A falls by 1 cm, then its volume decreases by 1 cm × 756.25 cm² = 756.25 cm³.

If the water level in Tank B rises by 1 cm, then its volume increases by 1 cm × 5 cm × 5 cm = 25 cm³.

We know moreover that the increase in volume of water in Tank B equals the decrease in volume of water in Tank A. Therefore:

(X - 20) × 25 = (28 - X) × 756.25.

Do the algebra:

⇒ (25 + 756.25) X = 28 × 756.25 + 20 × 25

⇒ 781.25X = 21675

⇒ X = 27.744.

Hope this helps and feel free to ask for any clarifications.

- Dr. Choo Yan Min

www.EconsPhDTutor.com

EconsPhDTutor
OrangeBelt
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### Re: Q&A - PSLE Math

dido wrote:Hi,

I am trying to help my P6 child in his Math revision, but I couldn't solve. Can someone help? Thanks a million.

God Bless
13. I interpret this question to be asking for the length of the perimeter of Figure 1 with which Ball A comes into contact, during its journey.

This length is highlighted in red, green, and blue colours in the figure below.

The red lengths on the left and right sides simply add up to 2 × 15 cm = 30 cm.

The green length on the upper side is 38 cm - 2 × 7 cm = 24 cm. The blue length on the upper side is half the circumference of the circle: π̶r̶=̶ ̶3̶.̶1̶4̶ ̶×̶ ̶7̶ ̶=̶ ̶2̶1̶.̶9̶8̶ I made a mistake here previously of using the diameter instead of the radius. Now corrected: πr= 3.14 × 7 × 0.5 = 10.99.

Altogether, the green and blue lengths on the upper side add up to 34.99 cm.

Symmetrically, the green and blue lengths on the lower side add up to 34.99 cm.

Altogether then, the total length is 30 + 34.99 + 34.99 = 99.98 cm.

Hope this helps and feel free to ask for any clarifications.

- Dr. Choo Yan Min

www.EconsPhDTutor.com

Last edited by EconsPhDTutor on Wed Jun 15, 2016 9:21 am, edited 1 time in total.

dido
OrangeBelt
Posts: 64
Joined: Sun Jul 05,

### Re: Q&A - PSLE Math

Hi Dr Choo,

Thanks so much for your help. For question 13, the answer in answer sheet is 99.98cm. I think it could be wrong, I am not sure. Nevertheless, we thank you for helping us solve it.

Thanks
Dido

speedmaths.com
BrownBelt
Posts: 559
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### Re: Q&A - PSLE Math

EconsPhDTutor wrote:
dido wrote:Hi,

I am trying to help my P6 child in his Math revision, but I couldn't solve. Can someone help? Thanks a million.

God Bless
13. I interpret this question to be asking for the length of the perimeter of Figure 1 with which Ball A comes into contact, during its journey.

This length is highlighted in red, green, and blue colours in the figure below.

The red lengths on the left and right sides simply add up to 2 × 15 cm = 30 cm.

The green length on the upper side is 38 cm - 2 × 7 cm = 24 cm. The blue length on the upper side is half the circumference of the circle: πr= 3.14 × 7 = 21.98.

Altogether, the green and blue lengths on the upper side add up to 45.98 cm.

Symmetrically, the green and blue lengths on the lower side add up to 45.98 cm.

Altogether then, the total length is 30 + 45.98 + 45.98 = 121.96 cm.

Hope this helps and feel free to ask for any clarifications.

- Dr. Choo Yan Min

www.EconsPhDTutor.com

Hi,

The blue length on the upper side is half the circumference of the circle:
πr= 3.14 × 7 x 1/2 = 21.98 x 1/2 = ???.

Cheers

speedmaths.com
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Sruthi
BlueBelt
Posts: 243
Joined: Thu Nov 12,

### Re: Q&A - PSLE Math

Hi friend,
I cant understanc the explanation ,why 13u is used and for male why it is divided into 5 parts and female 6 parts . Can you please help to explain ?

dido
OrangeBelt
Posts: 64
Joined: Sun Jul 05,

### Re: Q&A - PSLE Math

Hi Speedmath,

Thanks for helping.

Regards