Q&A - P3 Math

[atutor2001]

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:

Don't draw the BEFORE diagram first.

Draw the AFTER diagram first then add back $180 and $200 to this AFTER diagram such that Karen is longer than Ali (this \"longer\" part is $40) and we will get the comparison model for BEFORE.

[ ][ ]...Karen (AFTER)
[ ].......Ali (AFTER)

[ ][ ][-----$180--------]...Karen (BEFORE)
[ ][-------$200-----]$40 ....Ali (BEFORE)

So 1 UNIT is 200+40-180 = 60

[KSP]

P3 Maths question.


x + y = 500
x - y = 300

Find x and y.

How to explain the whole process of solving this to a P3? Thanks.

[atutor2001]

KSP:

P3 Maths question.


x + y = 500
x - y = 300

Find x and y.

How to explain the whole process of solving this to a P3? Thanks.

Hi KSP

Good question because many kids do not understand x-y in model. Draw x longer than y and the difference is 300. So x-y gives the \"difference\" in length of the model between X & Y where X is longer than Y. In words, (x-y=300) means X is 300 more than Y

[......................] ----X
[........]....300.... ----Y

[bookwormkids]

atutor2001:

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:

Don't draw the BEFORE diagram first.

Draw the AFTER diagram first then add back $180 and $200 to this AFTER diagram such that Karen is longer than Ali (this \"longer\" part is $40) and we will get the comparison model for BEFORE.

[ ][ ]...Karen (AFTER)
[ ].......Ali (AFTER)

[ ][ ][-----$180--------]...Karen (BEFORE)
[ ][-------$200-----]$40 ....Ali (BEFORE)

So 1 UNIT is 200+40-180 = 60

Hi atutor2001! Thanks for your help!

[atutor2001]

bookwormkids:

Hi atutor2001! Thanks for your help!

You are most welcome. I find it easier to draw backwards from comparison model with \"complete unit\" then starting with \"difference\".

[Alex001]

Sorry, I originally written an item that was not related to the question. I apologize for this message.

[usaik]

Hi,

The following question is from one of the top school past year paper for P4. I need help on the way how working can be worked out for the question. Many thanks in advance please.

The answer provided is \"C\"

http://postimage.org/image/1p1t773s4/

[tianzhu]

usaik:

Hi,

The following question is from one of the top school past year paper for P4. I need help on the way how working can be worked out for the question. Many thanks in advance please.

The answer provided is \"C\"

http://postimage.org/image/1p1t773s4/

Hi usaik

Good Morning.

Look at the pattern; the multiples of 3(even) like 6, 12, 18 appear in Row A.

The multiples of 3 (odd) like 3, 6, 9 ….. appear in Row C.

The nearest multiple of 3 to the number 100 is 99. It is odd,therefore,should be in Row C.

The number 100 appears to the right of 99 which is in Row C.

Hence , the given answer is correct.

Best wishes

[plum-cake]

KSP:

P3 Maths question.


x + y = 500
x - y = 300

Find x and y.

How to explain the whole process of solving this to a P3? Thanks.

Can't we do like this
x + Y = 500 --------statement 1
x - y = 300 --------Statement 2

then statement 1 - statement 2
that is
(x - x) (y - -y) = (500 -300)

so x will get cut off and y will become 2ys ( minus minus will be plus) = 200
that is 2y = 200
y = 100

now according to statement1
x + 100 = 500
x = 500- 100
= 400

same Question came in the P2 paper but for the x,y they put star and moon pictures. with the help of another mommy I tried to explain with the bar. but my daughter couldn't understand but with the above method she got something...

my question is Is it wrong?

[usaik]

tianzhu:

usaik:

Hi,

The following question is from one of the top school past year paper for P4. I need help on the way how working can be worked out for the question. Many thanks in advance please.

The answer provided is \"C\"

http://postimage.org/image/1p1t773s4/

Hi usaik

Good Morning.

Look at the pattern; the multiples of 3(even) like 6, 12, 18 appear in Row A.

The multiples of 3 (odd) like 3, 6, 9 ….. appear in Row C.

The nearest multiple of 3 to the number 100 is 99. It is odd,therefore,should be in Row C.

The number 100 appears to the right of 99 which is in Row C.

Hence , the given answer is correct.

Best wishes

Hi Tianzhu,
Thank you so much! Hope you have a good evening...