Q&A - PSLE Math

[tianzhu]

Belle2011:

Kelly had 5100 beads. 20% of them were red. After Carol gave her some more red beads, the percentage of red beads increased to 40%.
How many red beads did Carol give Kelly?
(model ans 6800)

Hi Belle

Good Morning.

I believe you are just checking the answer.

6800 is the total number of beads after the addition of some red beads.

Carol gave 1700 red beads to Kelly.

Best wishes

[Belle2011]

tianzhu:

Belle2011:

Kelly had 5100 beads. 20% of them were red. After Carol gave her some more red beads, the percentage of red beads increased to 40%.
How many red beads did Carol give Kelly?
(model ans 6800)

Hi Belle

Good Morning.

I believe you are just checking the answer.

6800 is the total number of beads after the addition of some red beads.

Carol gave 1700 red beads to Kelly.

Best wishes

Dear tianzhu,
My ans is 1700 but the model ans is 6800. That is why I have to ask the si-fus here.
So your ans is also 1700 ie Carol gave 1700 red beads to Kelly?
Thank-you.

Cheers,
Belle.

[tianzhu]

Belle2011:

Dear tianzhu,

My ans is 1700 but the model ans is 6800. That is why I have to ask the si-fus here.
So your ans is also 1700 ie Carol gave 1700 red beads to Kelly?
Thank-you.

Cheers,
Belle.

Hi Belle

You're welcome.

Yes, my answer is 1700.

But I’ve to sound it out; I am not a sifu, so use my answer with your eyes wide open.

I am just a victim of circumstances.

Best wishes

[Apphia]

Hello Tianzhu,


Thank you for the detailed and colourful presentation.

My daughter loves it n she definitely sees the steps so much clearer.

[tianzhu]

Apphia:

Hello Tianzhu,


Thank you for the detailed and colourful presentation.

My daughter loves it n she definitely sees the steps so much clearer.

Hi Apphia

Good Morning.

You're welcome.

I am happy your daughter liked it.

Best wishes

[tianzhu]

Apphia:

2) Julian had 300 more cards than Faizal. Julian gave 3/5 of his cards to Faizal. Faizal then gave 1/4 of the total number of what he had then to Julian. In the end, Fazial had 300 more cards than Julian. How many cards did Julian have at first?

Hi Apphia

Your second question has been discussed in one of the earlier posts.You may use UM or MD to solve it.

Here's the UM solution which I had posted earlier.

Best wishes

http://farm6.static.flickr.com/5248/5301831898_a925296513_b.jpg\">

[babyluvv]

Need help


1) Box A contained 134 marbles and Box B contained 18 marbles at first. An equal number of marbles was added to each box. As a result of this, the number of marbles in A to the number of marbles in B became 5 : 1.
a) How many marbles were added to each box?
b) Next, some marbles were transferred from Box A to Box B so that there was an equal number of marbles in each box. How many marbles were there in each box in the end?

2) 7/12 of the guests in a party are adults. The ratio of the number of boys to the number of girls is 6 : 9. respectively. There are 144 more adults than girls. What is the total number of guests at the party?

[tianzhu]

babyluvv:

1) Box A contained 134 marbles and Box B contained 18 marbles at first. An equal number of marbles was added to each box. As a result of this, the number of marbles in A to the number of marbles in B became 5 : 1.
a) How many marbles were added to each box?
b) Next, some marbles were transferred from Box A to Box B so that there was an equal number of marbles in each box. How many marbles were there in each box in the end?

2) 7/12 of the guests in a party are adults. The ratio of the number of boys to the number of girls is 6 : 9. respectively. There are 144 more adults than girls. What is the total number of guests at the party?

Hi

For the benefits of other members, it may be useful to indicate if the questions are for P5 or P6.

A quick one

For Q1, a student should note that the difference in the number of marbles between Box A and box B remains the same before and after as equal number of marbles are added to each box.

You may solve it with MD.

4 units ----- 134 – 18 ----- 116
1 unit ----- 29

a) 29 – 18 ------ 11

b) 3 units ------ 3*29 -----87

For Q2, you may do it with MD.

Draw a box and divide into 12 units.

7 units ------ adults
5 units ------children(boys and girls)

Boys: Girls ------ 6:9 --------2:3
Therefore, 2 units ------ boys and 3 units ------- girls

7 - 3 ------ 4

4 units -------- 144
1 unit ------- 36

12 units ------432

Hope this helps.

Best wishes

[babyluvv]

Thanks for the prompt response, Tianzhu.

Okies… its a P6 Maths question.

[tianzhu]

babyluvv:

Thanks for the prompt response, Tianzhu.

Okies.. its a P6 Maths question.

Hi babyluvv

You're welcome.

Have a nice weekend.

Best wishes