Q&A - PSLE Math

[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:

[corneyAmber]

bobsg01:

Thank you ksi.


:celebrate:

U r :welcome:

[Brenda10]

ksi:

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

Dear KSI

Thank you for your explanation as this help us to verify the answer.

[corneyAmber]

Brenda10:

Dear KSI

Thank you for your explanation as this help us to verify the answer.

You are :welcome: Brenda....your dd is GOOD!! *thumbs up* :salute:

[Brenda10]

ksi:

Brenda10:

Dear KSI

Thank you for your explanation as this help us to verify the answer.

You are :welcome: Brenda....your dd is GOOD!! *thumbs up* :salute:

:oops: The Maths quesiton is getting tougher and 千变万化. DD still have long way to learn lah.

[corneyAmber]

Brenda10:

ksi:

[quote=\"Brenda10\"]
Dear KSI

Thank you for your explanation as this help us to verify the answer.

You are :welcome: Brenda....your dd is GOOD!! *thumbs up* :salute:

:oops: The Maths quesiton is getting tougher and 千变万化. DD still have long way to learn lah.[/quote]If her foundation is strong, should be no issue cos she has already learned how to fish. :boogie: