Tutor MathsGuru: Ask me for your burning Maths questions!

[YLH88]

Hi Mathsguru, Coffeecat,


Thank you very much for the solution!!

[quote]ChiefKiasu wrote:
mathsguru, just as a small token of our appreciation for the help you have rendered to our community, we award you 5000 KPs for you kind contributions! [/quote]Congratulations, Mathsguru!!

[starlight1968sg]

Thanks Vanilla Cake for your help.

[Tiramisu Coco]

Hi mathsguru,


Need your help to solve this problem sum:

Roger had $186 more than Belinda. When he gave $20 to Belinda he still had three times as much money as she. How much did Roger have at first?

Thanks.

[small]

Tiramisu Coco:

Hi mathsguru,


Need your help to solve this problem sum:

Roger had $186 more than Belinda. When he gave $20 to Belinda he still had three times as much money as she. How much did Roger have at first?

Thanks.

Hi Tiramisu Coco,

Hope this helps.

http://www.postimage.org/image.php?v=Tsam0SJ

http://s2.postimage.org/am0SJ-18ffc60624acee8a1987811adf37b4e9.png\">

[chanpy]

Tagged as challenging question for P2 -


Mary baked 34 cupcakes for her friends. She packed 4 cupcakes into each bag. What is the greatest number of bags she needed to pack all the cupcakes?

What would be your answer - 8 or 9 bags?

The answer given by the teacher is 8 bags.

Appreciate advice on how to explain to kid.

TIA

[Muffins]

Hi chanpy, the correct answer is 9 bags. As there are 4 cupcakes in each bag, 4X8=32 only, not 34, so the next number of bags would be 9! :shock: :yikes:

[Tiramisu Coco]

small:

Tiramisu Coco:

Hi mathsguru,


Need your help to solve this problem sum:

Roger had $186 more than Belinda. When he gave $20 to Belinda he still had three times as much money as she. How much did Roger have at first?

Thanks.

Hi Tiramisu Coco,

Hope this helps.

http://www.postimage.org/image.php?v=Tsam0SJ

http://s2.postimage.org/am0SJ-18ffc60624acee8a1987811adf37b4e9.png\">

Hi small,

Thks for your help. But I still have some queries.
According to your workings, Roger have $249 at first.
So, after he gave $20 to Belinda, he will have $229.
This $229 should be 3 times the amount Belinda has after
Roger had given her $20.
However, Belinda has $63 + $20 = $83, after Roger gave her $20.
3 x $83 = $249. (Not $229).

I feel that the difference between Roger and Belinda, after Roger gave Belinda $20, should be $186 - $40 = $146 instead of $166 as Roger has
reduced by $20 and Belinda has increased by $20. Thus the net difference is reduced by $40.

Maths Guru, hope you can help to solve this problem.

Thanks!

[Guan Hui]

I think small forgot to minus of the $20 from roger. (you can see from his model, roger's bar is still equally long after minus-ing $20)

since belinda amount +20 and roger amount -20 their new difference in amount should be 186-40=146.
The rest is the same..
2u + 40= 146
2u= 106
u=53
roger have 53+ 186= $239 at first.
(pls add dollar signs where ever you deem applicable ) :lol: :lol:

[small]

Tiramisu Coco,


Apologies for my mistake. Please find the attached correct method.

http://www.postimage.org/image.php?v=Pq15Xj9

[Tiramisu Coco]

Hi Guan Hui & small,


Thks for your help, now I hv got a clearer picture.