Q&A - PSLE Math

[PiggyLalala]

PiggyLalala:

Saw this infamous PSLE 2009 question on a tuition centre leaflet. Decided to post in here before I throw the leaflet away. :razz:


'Jim bought some chocolates and gave half of it to Ken. Ken bought some sweets and gave half of it to Jim. Jim ate 12 sweets and Ken ate 18 chocolates. The ratio of Jim's sweets to chocolates became 1:7 and the ratio of Ken's sweets to chocolates became 1:4. How many sweets did Ken buy?' Answer: 68 sweets.

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After learning from all the Maths Experts in this forum, here is first attempt in solving a complicated word problem using model. Hope the model and the solution make sense.

[adanial]

Hi,


I'm a newbie here. Not too sure if anyone can help to solve P6 maths problem sum. shd I be posting the questions here. ?

I'm frustrated that I cant help him out in his revision.

pls help

[Brenda10]

Hi, need help as we have a question that can work out the answer (same with answer key) but not sure how to verify.


SGC 2010 Prelim Q13.

Terry bought a vase which he decides to sell. If he sells thh vase at a discount of 20%, he makes a gain of $150. if he sells it at a 45% discount, he loses $325. How much did Terry pay for this vase?

DD working:

45 - 20 = 25
325 + 150 = 475
475 / 25 = 19

80 x 19 - 150 = $1370
55 x 19 + 325 = $1370

How to use this amount $1370 to verify the above statement that he gain or loses ?

Thank you.

[bobsg01]

P6 math problem. :imdrowning:


Thanks for any help rendered.

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[VisualTextEducation]

Yes. you can post the Question here. I dont mind solving it for you=)

[corneyAmber]

Brenda10:

Hi, need help as we have a question that can work out the answer (same with answer key) but not sure how to verify.


SGC 2010 Prelim Q13.

Terry bought a vase which he decides to sell. If he sells thh vase at a discount of 20%, he makes a gain of $150. if he sells it at a 45% discount, he loses $325. How much did Terry pay for this vase?

DD working:

45 - 20 = 25
325 + 150 = 475
475 / 25 = 19

80 x 19 - 150 = $1370
55 x 19 + 325 = $1370

How to use this amount $1370 to verify the above statement that he gain or loses ?

Thank you.

Dear Brenda,

$1370 is the cost price.
She needs to substitute the values in the selling price equation to find that the selling price is the same for checking.

0.8 x sp = 1370+150 = 1520
sp =1520/0.8 = $1900

0.55 x sp = 1370-325 = 1045
sp = 1045/0.55 = $1900

[corneyAmber]

bobsg01:

P6 math problem. :imdrowning:


Thanks for any help rendered.

http://i52.tinypic.com/2regq39.jpg\">

5 cubes + 3 balls = 300
2 cones + 2 balls = 220
1 cone = 2 cubes
1 cube + 1 ball = 300-220 = 80 ---(1)
Since 2 cones + 2 balls = 220,
1 cone + 1 ball = 110
substitute 1 cone = 2 cubes,
2 cubes + 1 ball = 110 --- (2)

(2)-(1),
1 cube = 30g
1 cone = 2 cubes = 60g
1 ball = 110-60 = 50g

[fsaith]

Hi I would like to know the solution of this question. Thanks so much in advance!


Siti has some dark chocolates and white chocolates in a container. If she eats 3 dark chocolates, the ratio of the number of dark chocolates to the number of white chocolates will become 5:4. If she eats 3 white chocolates, the ratio of the number of dark chocolates will then be 7:5. What is the original number of dark chocolates and white chocolates in the container?

[adanial]

Hi YellowBelt, here is the question…thanks for your help.


Question 1
Loyang electronic store sold television sets, fans and washing machines.
2/5 of the items in the store were television sets. 12.5% of the remainder were fans and the rest were washing machines. During a sale held in december, the number of televsion sets sold to the number of fans sold to the number of washing machnes sold was 3:2:4. Altogether 3/4 of the items in the store were sold and $34070 was collected from the sale of all the items.
The table below shows teh average selling price of the 3 items in loyang electronic store :

TV set - $1350
Fan - $102
Washing m/c - $640

How many washing machines were on sale at first ?


Question 2
Julie had to complete a jigsaw puzzle. On thefirst day, she managed to complete 20% of the puzzle. On the second day she fitted another 60 pc of the puzzle. As a result, the ratio of the number of fitted pieces to the ration of the number of unfitted pieces became 2:5. How many pieces did the jigsaw puzzle consist of ?

[bobsg01]

Thank you ksi.


:celebrate: