Q&A - P3 Math

[Muffins]

Hi small,


just wondering, if multiples of numbers are their numbers that have been multiplied to give the result, wouldn’t the multiples of 11 (6+5) be 11, 22, 33 etc.

sorry for the inconvenience, but couldya pls explain? cannot understand…

[usaik]

Hi,


I need help with the following question. Many thanks in advance!

Jim had 2346 coins. He gave away 27 coins and his friend gave him 628 new coins. He then put the coins equally into 4 boxes.
(a) what was the greatest possible number of coins in each box?
(b) how many coins were left over?

[Muffins]

2346 - 27 = 2319


2319 + 628 = 2947

Rounding down 2947 to the nearest multiple of 4, we get 2944

So, the answer for a) is 2944

b) 2947 - 2944 = 3

Hope this helped!

[small]

Muffins:

Hi small,


just wondering, if multiples of numbers are their numbers that have been multiplied to give the result, wouldn't the multiples of 11 (6+5) be 11, 22, 33 etc.

sorry for the inconvenience, but couldya pls explain? cannot understand....

Hi Muffins,

From the question: If he gives each friend 6 pokemon cards, he will have 5 cards left.

It means the number will be multiple of 6 cards + 5 cards.

n=1; 6 x 1 + 5 = 11
n=2; 6 x 2 + 5 = 17
n=3; 6 x 3 + 5 = 23


Hope this helps..

[small]

Muffins:

2346 - 27 = 2319


2319 + 628 = 2947

Rounding down 2947 to the nearest multiple of 4, we get 2944

So, the answer for a) is 2944

b) 2947 - 2944 = 3

Hope this helped!

I think Muffins forgot to divide the total coins by 4:

2346 - 27 + 628 = 2947

2947 / 4 = 736 R3

a) 736 coins
b) 3 coins

.

[usaik]

small:

Muffins:

2346 - 27 = 2319


2319 + 628 = 2947

Rounding down 2947 to the nearest multiple of 4, we get 2944

So, the answer for a) is 2944

b) 2947 - 2944 = 3

Hope this helped!

I think Muffins forgot to divide the total coins by 4:

2346 - 27 + 628 = 2947

2947 / 4 = 736 R3

a) 736 coins
b) 3 coins

.

Hi Muffin, Hi Small,
Thanks for the enlightenment.
I initially thought I have to use esimate to solve this and was stuck for a long while. THANKS so much!!!

[pertunia]

small:

Hassan has some pokemon cards to share among his friends. If he gives each friend 6 pokemon cards, he will have 5 cards left. If he gives each friend 8 pokemon cards, he will be short of 7 pokemon cards. How many pokemon cards does Hassan have? \t\t\t\t\t


Gap : 5+7 = 12

Different = 8 - 6 = 2\t\t\t\t\t\t\t\t
12 / 2 = 6 friends\t\t\t\t\t
\t\t\t
From red font :
6 cards x 6 + 5 cards
= 41 cards\t\t\t\t\t\t

Hassan have 41 pokemon cards altogether.

Hi small,

Can you please explain why you use gap = 5+7? I am missing something here. Thanks.

And thanks to all the others who help with the answers. Really appreciate it.

[small]

pertunia:

small:

Hassan has some pokemon cards to share among his friends. If he gives each friend 6 pokemon cards, he will have 5 cards left. If he gives each friend 8 pokemon cards, he will be short of 7 pokemon cards. How many pokemon cards does Hassan have? \t\t\t\t\t


Gap : 5+7 = 12

Different = 8 - 6 = 2\t\t\t\t\t\t\t\t
12 / 2 = 6 friends\t\t\t\t\t
\t\t\t
From red font :
6 cards x 6 + 5 cards
= 41 cards\t\t\t\t\t\t

Hassan have 41 pokemon cards altogether.

Hi small,

Can you please explain why you use gap = 5+7? I am missing something here. Thanks.

And thanks to all the others who help with the answers. Really appreciate it.

Hi pertunia,

I am using Inference Approach to solve this, learned this from my son. :oops:


Alternatively you can refer to Tianzhu's solution on other question. :celebrate:

http://www.kiasuparents.com/kiasu/forum/viewtopic.php?t=280&postdays=0&postorder=asc&start=2490

.

[usaik]

small:

Hi pertunia,

I am using Inference Approach to solve this, learned this from my son. :oops:

Hi Small,
Are inference approach taugth in school?
My child is able to solve this but too impatient to show me the detailed working :x . But I manage to conclude that he did it via the difference of the cards given to the friend and the difference of the cards left to deduce the no of friends. I am pretty sure this is a faster method compared to the traditional algebra method I was taught as the child is able to achive it mentally without any working rather quickly. But my concern is his lack of working may cause him to lose mark.


Hi Pertunia,
I can only achieve this via the algebra way which help me to understand how this gap thingy way works. If you were also trained in the way how I was trained perhaps this working might help you understand what the gap means.

No of friends : n
6n +5 = total number of cards........(1)
8n - 7= total number of cards ........(2)

(2) - (1) : 2n -7-5 = 0 => 2n = 7+5 => n = 6

No of cards Hassan has : 6x6 + 5 = 41

[bookwormkids]

Hi! Need help on the following question (Q35).


Karen had $40 more than Ali. After Karen bought a dress for $180 and Ali bought a tennis racket for $200, Karen had twice the amount of money Ali had. How much did Karen has at first?

Could anyone provide solution with model drawing please? (I don't really know how to draw the \"after\" diagram.) Thanks!

:oops: