Q&A - P5 Math

[Bolt]

Please help


16) There are some crystal and glass marbles in a pouch. If 3 crystal marbles are removed from the pouch, the number of crystal marbles left will be 1/6 of the glass marbles left. If 5 glass marbles are removed from the pouch, the number of crystal marbles left will be 1/4 of the glass marbles left. How many marbles are there in the pouch at first?

[MANGO STAR]

Hi,


can someone pls help with this question.

Weichong and Rama collect stamps. If Rama gives Weichong 15 stamps, he will have the same number of stamps as Weichong. If Weichong gives Rama 15 stamps, he will have 1/2 as many stamps as Rama. How many stamps does each boy have?

[tianzhu]

MANGO STAR:

Hi,


can someone pls help with this question.

Weichong and Rama collect stamps. If Rama gives Weichong 15 stamps, he will have the same number of stamps as Weichong. If Weichong gives Rama 15 stamps, he will have 1/2 as many stamps as Rama. How many stamps does each boy have?

Hi

Hope this helps.

Best wishes.

http://farm8.staticflickr.com/7043/7134329007_e0a139ea17_z.jpg\">

[MathIzzzFun]

Bolt:

Please help


16) There are some crystal and glass marbles in a pouch. If 3 crystal marbles are removed from the pouch, the number of crystal marbles left will be 1/6 of the glass marbles left. If 5 glass marbles are removed from the pouch, the number of crystal marbles left will be 1/4 of the glass marbles left. How many marbles are there in the pouch at first?

hi
the question is not set properly - as it is, the number of marbles is not a whole number. I suspect the sentence \"the number of crystal marbles left will be 1/6 of the glass marbles left.\" should instead be \"the number of crystal marbles left will be 1/6 of the marbles left.\"

any way, here is the solution for the question as is, using MD...

http://i50.tinypic.com/2u9ua9x.png\">

cheers.

[MANGO STAR]

Hi Tianzhu,


thank you so much. I’ve been cracking my head with this sum but u jus solve it so easily. I think i have to go to sch with my son liao !!! Hahaha!!

My old rusty brain.

[tianzhu]

MANGO STAR:

Hi Tianzhu,


thank you so much. I've been cracking my head with this sum but u jus solve it so easily. I think i have to go to sch with my son liao !!! Hahaha!!

My old rusty brain.

Hi

You’re welcome.

Sometimes life leaves us with no choice but to “go to school with our kids”.

Enjoy the journey.

Best wishes

[Bolt]

thank you, got it.

[Barbara Ng]

Thanks Tianzhu for your prompt reply. Really appreciated.

[concerned1970]

tianzhu:

S6169:

Sorry, a bit confuse here,
\"Each piece cut from Rope Q was 2/5 longer than each piece cut from Rope P\", 2/5 is fraction or refer to 2/5 m?
If it refer to the fraction, then should be 2*(1+2/5)=2.8m

Hi

Thank you for pointing out the error.

It should be 2/5 (fraction) not 2.5m

2.8 m is the correct answer.

Best wishes

Hi!

So sry just realized that I'd made a mistake. It's 2/5m longer. So what should be the correct answer?

[concerned1970]

mummyv:

Udon:

Appreciate some help on the following questions...


1) It takes 3 cleaners 2/9 h to clean an office. How long do 5 cleaners take to clean the same office, assuming every cleaner clean at the same rate?

hi

3 cleaners => 2/9 h
1 cleaner => 2/9 h x 3 = 2/3 h
5 cleaners => 2/3 ÷ 5 = 2/15 h

Hi, i don't get it why was that 1 cleaner is 2/9h x 3 and not 2/9h divided by 3? (sry couldn't find the division sign on iPad.)