Q&A - PSLE Math

[corneyAmber]

bobsg01:

:yikes: So sorry ksi, didn't read carefully enough.


Thanks for the patience and kind explanation ksi.

:imcool: Your Math knowledge are simply cool. :salute:

Not a problem, you are most :welcome:

[JadeDry]

Hello again, I have a problem that I am unsure about:


Simplify the following expression:

3/4((x squared)(y)) X 5/9((x)(z cubed)) / ((20/9)(x quadrupled)(y squared)(z))

These are my workings:
3/4((x squared)(y)) X 5/9((x)(z cubed))=

15/36((x cubed)(y)(z cubed))


15/36((x cubed)(y)(z cubed)) / ((20/9)(x quadrupled)(y squared)(z))=

3(Z squared) / 16(xy)

Are my calculations correct?

On a side note, is Z cubed/ Z= Z squared or Z cubed?

Thanks in advance.

[corneyAmber]

JadeDry:

Hello again, I have a problem that I am unsure about:


Simplify the following expression:

3/4((x squared)(y)) X 5/9((x)(z cubed)) / ((20/9)(x quadrupled)(y squared)(z))

These are my workings:
3/4((x squared)(y)) X 5/9((x)(z cubed))=

15/36((x cubed)(y)(z cubed))


15/36((x cubed)(y)(z cubed)) / ((20/9)(x quadrupled)(y squared)(z))=

3(Z squared) / 16(xy)

Are my calculations correct?

On a side note, is Z cubed/ Z= Z squared or Z cubed?

Thanks in advance.

Your answer is correct.

Z cube / Z = Z square because it is equal to ZZZ/ Z = ZZ

[zsqchx]

Can someone help for this question. Thanks.


Candle A and Candle B are of the same length. Candle A, Which is broader, can burn for 5h while Candle B, the thinner candle, can burn for 4h. If both candles are lighted at the same time, how long does it take for Candle A to be twice as long left as Candle B?

[MathIzzzFun]

zsqchx:

Can someone help for this question. Thanks.


Candle A and Candle B are of the same length. Candle A, Which is broader, can burn for 5h while Candle B, the thinner candle, can burn for 4h. If both candles are lighted at the same time, how long does it take for Candle A to be twice as long left as Candle B?

Hi zsqchx,

This is a speed question phrased in an interesting way. The question is asking for the time to burn such that the remaining length of Candle A will be twice that of B.

http://i53.tinypic.com/t7z701.jpg\">


.. if it is referring to time to burn such that time left to burn the remaining length of A is twice that of B, then the answer will be slightly different - in this case, time to burn is 3h, so that time left to burn remaining length A = 2h, and time left to burn remaining length of B =1h.


cheers.

[stary]

what is the number of times for each ranking?


Kiasu Newbie -> 0-10
Yellow -> 11-???
…
…
Black -> ???-1000

[P5G]

Please help.


http://www.orlesson.org/orp/10Ma/2010-P6-Math-SA2-Nanyang.pdf

17. There were some blue marbles and white marbles in a bag. If 70 blue marbles were to be removed from the bag, the ratio of the number of blue marbles to the number of white marbles would be 3 : 4. If 112 white marbles were to be removed from the bag instead, the ratio of the number of blue marbles to the number of white marbles would be 8 : 7. When 48 more blue marbles were to be added into the bag, what percentage of all the marbles would be blue marbles?

TIA.

[MathIzzzFun]

P5G:

Please help.


http://www.orlesson.org/orp/10Ma/2010-P6-Math-SA2-Nanyang.pdf

17. There were some blue marbles and white marbles in a bag. If 70 blue marbles were to be removed from the bag, the ratio of the number of blue marbles to the number of white marbles would be 3 : 4. If 112 white marbles were to be removed from the bag instead, the ratio of the number of blue marbles to the number of white marbles would be 8 : 7. When 48 more blue marbles were to be added into the bag, what percentage of all the marbles would be blue marbles?

TIA.

Hi P5G,

hope this helps

http://www.flickr.com/photos/62167097@N02/5884185905/in/photostream

cheers.

[zsqchx]

Hi MathIzzzFun ,


Thank you for your help!

[MathIzzzFun]

zsqchx:

Hi MathIzzzFun ,


Thank you for your help!

u r welcome

cheers.