Q&A - PSLE Math

[Mary Joy]

Please help to solve this questions…


1)Indriani had a bag of assorted candies.1/3 of the candies were lollipops and the rest were candy canes.She shared the lollipops equally among the boys such that each boy received 1/9 of the assorted candies.She then shared the candy canes equally among the girls such that each girl received 1/6 of the assorted candies.Find the number of boys and the number of girls.

2)Adam and Rahman shared some beads.If Adam gave 1/3 of his share to Rahmad,Rahmad would have 70 more than Adam.If Adam gave 1/5 of his share to Rahmad,Rahmad would have 10 more than Adam.How many beads does Adam have at first?

3)During the school holidays,Chris read 312 pages of a book at first.He read the remaining pages in 20 days,with the same number of pages each day.During these 20 days,he read 1/12 of the book in 6 days.How many pages of the book did he read in the 6 days?

[MathIzzzFun]

Mary Joy:

Please help to solve this questions...


1)Indriani had a bag of assorted candies.1/3 of the candies were lollipops and the rest were candy canes.She shared the lollipops equally among the boys such that each boy received 1/9 of the assorted candies.She then shared the candy canes equally among the girls such that each girl received 1/6 of the assorted candies.Find the number of boys and the number of girls.

Number of boys = 1/3 ÷ 1/9 = 3
Number of girls = 2/3 ÷ 1/6 = 4

cheers.

[MathIzzzFun]

Mary Joy:

Please help to solve this questions...



2)Adam and Rahman shared some beads.If Adam gave 1/3 of his share to Rahmad,Rahmad would have 70 more than Adam.If Adam gave 1/5 of his share to Rahmad,Rahmad would have 10 more than Adam.How many beads does Adam have at first?

same as this question -
\"If David after giving 1/3 of his money to Ken, Ken will have $70 more than David.
If David after giving 1/5 of his money to Ken, Ken will have $10 money than David. How much does David have initially?\"

- http://www.kiasuparents.com/kiasu/forum/viewtopic.php?f=69&t=280&start=8620

cheers.

[MathIzzzFun]

Mary Joy:

Please help to solve this questions...



3)During the school holidays,Chris read 312 pages of a book at first.He read the remaining pages in 20 days,with the same number of pages each day.During these 20 days,he read 1/12 of the book in 6 days.How many pages of the book did he read in the 6 days?

1/12 = 6/72
6 days --> 6/72 book
1 day --> 1/72 book
20 days --> 20/72 book
1-20/72 = 52/72

52/72 book --> 312 pages
1/72 book --> 6 pages

6 days --> 6/72 book --> 36 pages

cheers.

[Mary Joy]

MathIzzzFun:

Mary Joy:

Please help to solve this questions...



3)During the school holidays,Chris read 312 pages of a book at first.He read the remaining pages in 20 days,with the same number of pages each day.During these 20 days,he read 1/12 of the book in 6 days.How many pages of the book did he read in the 6 days?

1/12 = 6/72
6 days --> 6/72 book
1 day --> 1/72 book
20 days --> 20/72 book
1-20/72 = 52/72

52/72 book --> 312 pages
1/72 book --> 6 pages

6 days --> 6/72 book --> 36 pages

cheers.

Thanks a lot MathizzFun

[timtamfan]

Hi, I suspect these questions may have been answered elsewhere already. Anway, I’ve asked my DD for help. I wouldn’t be able to do them myself ha ha.


1) If you share 1/3 of the candies (all the lollipops) with ? boys so they each have 1/9 of the candies, there are 3 boys as 1/3 / 1/9 = 3.
If you share 2/3 of the candies (the remainder) with ? girls so they each have 1/6 of the candies, there are 4 girls as 2/3 = 4/6>

2) Take A as Adam’s original number of beads.
(70-10)/ 2=1/3 A - 1/5 A
30\t = 2/15 A
A\t = 225
Adam had 225 beads at first

3) He can read 1/12 /6 = 1/ 72 of the book in a day and 20/ 72 (5/ 18) of the book in the 20 days.
1 - 5/ 18\t = 13/18 of the book
\t\t→ 312 pages
1\t\t→ 432 pages in the book
432 x 1/12\t→ 36
Chris read 36 pages in the 6 days

[sing_xiangxiang]

Anybody can help to solve n explain below qn?

At statio A, the ratio of the number of children to the number of adults on a train was 4:5. At the next station, 12 children alighted and 10 adults boarded the train. The ratio of the number of children to the number of adults on the train then became 7:10. How many children were on the train at first?

[MathIzzzFun]

sing_xiangxiang:

Anybody can help to solve n explain below qn?

At statio A, the ratio of the number of children to the number of adults on a train was 4:5. At the next station, 12 children alighted and 10 adults boarded the train. The ratio of the number of children to the number of adults on the train then became 7:10. How many children were on the train at first?

this was discussed in an earlier post (pg 639)... http://www.kiasuparents.com/kiasu/forum/viewtopic.php?f=69&t=280&p=772802&hilit=12+children+alighted#p772802

cheers.

[oceanh2o]

Please help me in this question:


Jenny spent 1/5 of her money and additional $4 on some books. She then spent 3/4 of the remaining money and additional $9 on some magazines . Given that she was left with $36, how much money did Jenny have at first ?

Thanks !

[MathIzzzFun]

oceanh2o:

Please help me in this question:


Jenny spent 1/5 of her money and additional $4 on some books. She then spent 3/4 of the remaining money and additional $9 on some magazines . Given that she was left with $36, how much money did Jenny have at first ?

Thanks !

work backwards...

$9+$36 --> 1/4 of remaining money
so, 1/4 of remaining money --> $45
remaining money --> $45 x 4 = $ 180

$180 + $4 --> 4/5 of money
so, 4/5 of money --> $184
Total amount of money Jenny had at first --> $ 184/4 x 5 = $230

alternatively, you can also use model.. from which the total amount of money at first --> $(1+9+36) x 5 = $230

cheers.