Q&A - PSLE Math

[Rockstar]

firebird:

Dear all


Good afternoon.

Please help me on the following P6 maths:

Anna, Belinda and Clare bought a vase and shared the cost equally among themselves. Clare did not bring her money, so Anna and Belinda paid for the vase first. Anna paid 0.25 more than what Belinda had paid. The following day, Clare paid her share to both Anna and Belinda.

a) Clare paid Belinda $6.55. How much did Clare pay Anna?

b) Clare's brother bought a similar vase at the same shop during a sale and was given a disconunt of 20% of the price that Clare and her friends paid for. How much did Clare's brother pay for the Vase?

Thank you
Firebird

This question can be solved easily with a model.

What they were supposed to pay.

A [ 1 unit ]

B [ 1 unit ]

C [ 1 unit ]


But they paid,

A [ 1 unit ][$6.55][0.25 units]

B [ 1 unit ][$6.55]

$6.55 +$6.55+0.25 units = 1 unit
0. 75 units=13.10

Clare paid $13.10 to Anna

b)

1 unit-------$13.10+$6.55= $19.65

3 units------$19.65 x 3 = $58.95

100% of the cost----$58.95

100%-20% of the cost -------58.95/100 x 80
80% of the cost------$47.16

Clare's brother paid $47.26 for the vase.


Are both my answers correct?

[Vanilla Cake]

leesf:

Hi, appreciate if you could help this question from Kong Hwa practice papers.

Is your child in Kong Hwa and is the best P6 class from BICEP?

leesf:

A car and a truck were travelling from Town X to Town Y which were 375km apart. the car set off 2 hours later than the truck but arrived 1 hr 20min earlier. If the speed of the truck was 50km/h, find the time taken by the car to catch up with the truck.

Car set off 2 hours later than truck but arrived 1 h 20 min earlier means difference = 3 h 20 min = 3⅓h
Time taken for truck to reach Town Y = 375÷50= 7½ h
Time taken for car to reach Town Y = 7½h - 3⅓h = 4⅙h (4 and 1/6 h)
Speed of the car = 375÷4⅙ = 90 km/h (375÷4 and 1/6 = 90 km/h)
Headstart by truck in 2 h = 50x2 = 100 km
Difference in speed = (90-50)km/h = 40 km/h
Time taken by the car to catch up with the truck = 100/40= 2½h

[Vanilla Cake]

firebird:

Dear all

Good afternoon.
Please help me on the following P6 maths:

Hi firebird,
Is this question from your DS's homework or from one of the top schools' 2010 P6 Prelim exam papers?

firebird:

Anna, Belinda and Clare bought a vase and shared the cost equally among themselves. Clare did not bring her money, so Anna and Belinda paid for the vase first. Anna paid 0.25 more than what Belinda had paid. The following day, Clare paid her share to both Anna and Belinda.
a) Clare paid Belinda $6.55. How much did Clare pay Anna?
b) Clare's brother bought a similar vase at the same shop during a sale and was given a disconunt of 20% of the price that Clare and her friends paid for. How much did Clare's brother pay for the Vase?

A : B : C
1 : 1 : 1
Multiply by 3
3 : 3 : 3

Total cost of the vase-> 9 units
Each person must pay 3 units

As C did not bring her money, A and B paid for the vase first in the ratio of :
A : B
1.25 : 1
Multiply by 4
5 : 4

Clare paid Belinda $ 6.55
4u-3u=u
u = $6.55

Clare paid Anna -> 5u-3u=2u
2u=2x$6.55 = $13.10
(a) Amount of money that Clare paid Anna = $13.10

Total cost of the vase = 9u = 9x$6.55=$58.95
Amount paid by Clare's brother after a discount of 20% -> 80/100x$58.95=$47.16
(b) Amount of money that Clare's brother paid for the vase = $47.16

I think this concept is called unchanged total, check it up in http://www.onsponge.com/forum/35-thinkingmathonsponge.html for similar questions or check with Chris Rogers.

Thks.

[firebird]

Dear Vanilla cake


You are really great.

The question was from Nan Hua SA 2010. Q15 paper 2.

Many thanks
Firebird

[abc_parent]

Hi there

Thanks for helping me with the 4 exam prelim papers.

Vanilla Cake,
I will try SCGS question paper again. The truth is I find all questions mind-boggling. Then I will post the questions if I have time.
Thanks for telling me the powerpoint tip but most of the times, I only have enough time to type the questions…working adult’s time is not as much as you like to think! Will do with people who know what I am referring and can respond. Otherwise, I will just have to make do with whatever I can, I guess.

[ganchiong]

Good morning everyone,


Need help for the following question:

2010 Singapore Hokkien Huay Kuan P6 Prelim Maths Paper 2 Q18

The figure below shows 2 completely-filled tanks being emptied of the water from 2 different taps.

The taps at Tank A and Tank B were turned on at 7 am and 8.30 am respectively, until both tanks were completely empty. At 11 am, the water level in both tanks was the same. At 12.30 pm, Tank B was completely empty and Tank A was only completely empty at 1 pm. If the rate of flow of water from each tap was constant throughout, what was the height of Tank A?

P.S. not sure how to download the picture: 2 Tanks A and B with Tank A taller by 5 cm.

Thank you very much.

[tianzhu]

ganchiong:

2010 Singapore Hokkien Huay Kuan P6 Prelim Maths Paper 2 Q18


The figure below shows 2 completely-filled tanks being emptied of the water from 2 different taps.

The taps at Tank A and Tank B were turned on at 7 am and 8.30 am respectively, until both tanks were completely empty. At 11 am, the water level in both tanks was the same. At 12.30 pm, Tank B was completely empty and Tank A was only completely empty at 1 pm. If the rate of flow of water from each tap was constant throughout, what was the height of Tank A?

P.S. not sure how to download the picture: 2 Tanks A and B with Tank A taller by 5 cm.

Hi ganchiong

Good Morning

This question has been discussed in one of the earlier posts.

Please follow this link.

http://www.kiasuparents.com/kiasu/forum/viewtopic.php?t=280&postdays=0&postorder=asc&start=1720

Best wishes

[ganchiong]

Hi tianzhu


Thank you so much for your response.

[leesf]

Thanks Vanilla cake for your solution, my child is not in the best class. He is just average.

[firebird]

Dear maths gurus


Good morning.

Please help me on the following Rosyth SA 2010 P6 maths:

1) How many sixths are there in 54? Given answer 324. Sure 54 X 6 =324
But please let me what this question is asking? Paper 1 Q17

2) Susanne spent $42 on an equal number of drinks and chicken wings.
Four drinks cost as much as 3 chicken wings. Five drinks cost $2.80 more
than 2 chicken wings. How many chicken wings did she buy? Paper 2 Q 9

3) Three boys, Aaron, Ben and Charlie shared the cost of a birthday present for their father on his birthday.
The ratio of Aaron’s share to the total of Ben’s and Charlie’s share was 1:3. The ratio of Ben’s share to the total of Aaron’s and Charlie’s share was 1:5. Charlie paid $50 more than Ben. Find the cost of the present.Paper 2 Q 11

4) The Quesion 15 Paper 2 has a diagram. Need to find the shaded figure.
Very sorry, I do not have the scanner to upload the question. Please help if you can.

Many thanks
Firebird