Q&A - PSLE Math

[MathIzzzFun]

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?

Hi

This is variatiion to typical \"transfer\" problem.

First, assume we start with situation after Siti has taken 3 dark chocolate ie initial = dark : white = 5 : 4. Then the situation of \"when Siti eats 3 white chocolate\" would become after exchanging 3 white chocolate for 3 dark chocolates, the ratio = 7:5

So we have :

initial, dark : white = 5 : 4 = 20u : 16u
after, dark : white = 7 : 5 = 21u : 15u

1u = 3
Initial, dark: white = 20 u : 16u = 60:48

need to add back the 3 dark chocolates

There were 63 dark chocolates and 48 white chocolates at first.

cheers.

[Brenda10]

tianzhu:

Brenda10:

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?

Hi Brenda10

There are two scenarios in your question.

The first one involves Terry selling at a discount of 20% from the usual price or marked price. In the second case, he sells at a discount of 45% from the usual price.

When the selling price of the vase is less than the usual price or marked price of the vase, a discount on the item is given.

The selling price of the vase in the two scenarios is different, only the usual price or marked price remains the same.

I’ve problem uploading the images at this moment, I’ll do it at a later time.

Best wishes

Thank you Tianzhu and do take your time.

[tianzhu]

Brenda10:

Thank you Tianzhu and do take your time.

Hi Brenda10.

Hope this helps.

Best wishes.

http://farm4.static.flickr.com/3325/5817158092_59fee6a1d8_z.jpg\">

http://farm6.static.flickr.com/5064/5816591015_a98e4eb5a1_z.jpg\">

[fsaith]

[quote]Hi


This is variatiion to typical \"transfer\" problem.

First, assume we start with situation after Siti has taken 3 dark chocolate ie initial = dark : white = 5 : 4. Then the situation of \"when Siti eats 3 white chocolate\" would become after exchanging 3 white chocolate for 3 dark chocolates, the ratio = 7:5

So we have :

initial, dark : white = 5 : 4 = 20u : 16u
after, dark : white = 7 : 5 = 21u : 15u

1u = 3
Initial, dark: white = 20 u : 16u = 60:48

need to add back the 3 dark chocolates

There were 63 dark chocolates and 48 white chocolates at first.

cheers.[/quote]Thank you so much for your help!

[MathIzzzFun]

fsaith:

[quote]Hi


This is variatiion to typical \"transfer\" problem.

First, assume we start with situation after Siti has taken 3 dark chocolate ie initial = dark : white = 5 : 4. Then the situation of \"when Siti eats 3 white chocolate\" would become after exchanging 3 white chocolate for 3 dark chocolates, the ratio = 7:5

So we have :

initial, dark : white = 5 : 4 = 20u : 16u
after, dark : white = 7 : 5 = 21u : 15u

1u = 3
Initial, dark: white = 20 u : 16u = 60:48

need to add back the 3 dark chocolates

There were 63 dark chocolates and 48 white chocolates at first.

cheers.

Thank you so much for your help![/quote]u r welcome :lol:

cheers.

[stary]

Dharma:

If Charles continued driving after reaching the finishing line, he would have covered an additional 45km in the same time that Tony took to finish the race.


Time taken by Charles to drive the additional 45km = 45km/(90km/h) = 0.5 hr
Therefore, Charles finished the race (reached the finishing line) ½ hr earlier than Tony.[9.05 a.m.]

Hi Dharma n ksi,

Thanks for the solution. I got it. Tony will be 1/2 hrs faster than Charles, so Charles will reach finishing line at 9:35 + 1/2 hrs = 10:05 am

CHEERS :dancing:

[Brenda10]

tianzhu:

Brenda10:

Thank you Tianzhu and do take your time.

Hi Brenda10.

Hope this helps.

Best wishes.

http://farm4.static.flickr.com/3325/5817158092_59fee6a1d8_z.jpg\">

http://farm6.static.flickr.com/5064/5816591015_a98e4eb5a1_z.jpg\">

Hi Tianzhu

Thank you for your wonderful picture and explanation. DD said she can understand and also like the presentation. :lol:

[WLRR]

Hello


Need help with the following question:

The total mass of Jane and Jacky is 101 kg and the total mass of Jacky and Jorine is 77 kg. Jane is twice as heavy as Jorine. What is the average mass of the three girls ?

[Hifive]

Hi


Maths problem - pls help…

Terry and John went shopping with a total of $198. Terry had $10 more than John. Terry spent 25% as much money as John. After which, he had twice as much money as John.
a) How much money did Terry bring for shopping?
b) How much money had Terry left after shopping?

Kindly help. Thanks in advance!

[corneyAmber]

WLRR:

Hello


Need help with the following question:

The total mass of Jane and Jacky is 101 kg and the total mass of Jacky and Jorine is 77 kg. Jane is twice as heavy as Jorine. What is the average mass of the three girls ?

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