Q&A - PSLE Math

[waterfall]

Need help with explanation, Tks

1) Polly had 360 dolls more than Ariel at first. After Polly gave away 1/4 of her dolls and Ariel gave away 2/3 of her dolls, they had 764 dolls altogether. How many dolls did they give away altogether?

2) Jon, Molly and Chris shared some sweets. The ratio of the total number of sweets received by Jon and Molly to the number of sweets received by Chris was 2:5. When Chris gave 25 sweets to Jon and 31 sweets to Molly, and Jon gave 12 sweets to Molly, each of them had the same number of sweets. Find the total number of sweets Jon had at first.

[Ender]

Need help with explanation, Tks

1) Polly had 360 dolls more than Ariel at first. After Polly gave away 1/4 of her dolls and Ariel gave away 2/3 of her dolls, they had 764 dolls altogether. How many dolls did they give away altogether?

Let Ariel = 12u
Polly=12u+360

After Poly gave 1/4, left 3/4 = 9u+270
After Ariel gave 2/3, left 1/3 = 4u

9u+270+4u = 764
13u+270=764
13u=494
u = 38

At 1st, Polly had = 12u+360 = 816
Polly gave away = 816/4= 204

At 1st Ariel had = 12u = 456
Ariel gave away (2/3)X456 = 304

Altogether they gave away 204+304= 508

2) Jon, Molly and Chris shared some sweets. The ratio of the total number of sweets received by Jon and Molly to the number of sweets received by Chris was 2:5. When Chris gave 25 sweets to Jon and 31 sweets to Molly, and Jon gave 12 sweets to Molly, each of them had the same number of sweets. Find the total number of sweets Jon had at first.

This question has been answered before, various solutions here,
http://www.kiasuparents.com/kiasu/forum ... 5#p1460005
http://www.kiasuparents.com/kiasu/forum ... 6#p1460276
http://www.kiasuparents.com/kiasu/forum ... 1#p1460941

[waterfall]

Need help with explanation, Tks

1) Polly had 360 dolls more than Ariel at first. After Polly gave away 1/4 of her dolls and Ariel gave away 2/3 of her dolls, they had 764 dolls altogether. How many dolls did they give away altogether?

Let Ariel = 12u
Polly=12u+360

After Poly gave 1/4, left 3/4 = 9u+270
After Ariel gave 2/3, left 1/3 = 4u

9u+270+4u = 764
13u+270=764
13u=494
u = 38

At 1st, Polly had = 12u+360 = 816
Polly gave away = 816/4= 204

At 1st Ariel had = 12u = 456
Ariel gave away (2/3)X456 = 304

Altogether they gave away 204+304= 508

2) Jon, Molly and Chris shared some sweets. The ratio of the total number of sweets received by Jon and Molly to the number of sweets received by Chris was 2:5. When Chris gave 25 sweets to Jon and 31 sweets to Molly, and Jon gave 12 sweets to Molly, each of them had the same number of sweets. Find the total number of sweets Jon had at first.

This question has been answered before, various solutions here,
http://www.kiasuparents.com/kiasu/forum ... 5#p1460005
http://www.kiasuparents.com/kiasu/forum ... 6#p1460276
http://www.kiasuparents.com/kiasu/forum ... 1#p1460941

tks!

[alfretztay]

Pls help. Tks !

Please help. Thank u

(a) D : E : Total
21u : 8u + 7 : 500
– 9u – 7
---------- --------
12u(3) : 8u(2)

21u + 8u + 7 -> 500
29u -> 493
1u -> 17
21u -> 357

(b) 12u -> 204
204 x 0.20 -> 40.80

Ans : (a) 357 coins; (b) $40.80.

[belnanna]

Please can someone solve this question with explanation not using algebra?
Would appreciate it.. Thanks so much in advance.

Nathan read 25 pages of a book in the morning.In the afternoon, he read 1/4 of the remaining pages of the book.He read the remaining 1/3 of the book at night. how many pages were there in the book?

[waterfall]

Q1. At8:30am, a motorcycle left town A for Town B travelling at 60km/h. 1 1/2 hour later, a car left town A travelling at 85km/h. The car overtook the motocycle midway between Town A and Town B, and reached Town B first.
B)What was the distance between town A & Town B?



Thanks !

[SAHMom]

Please can someone solve this question with explanation not using algebra?
Would appreciate it.. Thanks so much in advance.

Nathan read 25 pages of a book in the morning.In the afternoon, he read 1/4 of the remaining pages of the book.He read the remaining 1/3 of the book at night. how many pages were there in the book?

[tianzhu]

Please can someone solve this question with explanation not using algebra?
Would appreciate it.. Thanks so much in advance.

Nathan read 25 pages of a book in the morning.In the afternoon, he read 1/4 of the remaining pages of the book.He read the remaining 1/3 of the book at night. how many pages were there in the book?

Hi belnanna

Good Evening.

The MD may be useful to your child.

I’ve drawn more MD than necessary; students may consolidate when they become more familiar.

5u ----- 25

1u ----- 5

9u ----- 45

I’ll leave it to your child to carry on with the details.

Hope this helps.

Best wishes.

[belnanna]

Please can someone solve this question with explanation not using algebra?
Would appreciate it.. Thanks so much in advance.

Nathan read 25 pages of a book in the morning.In the afternoon, he read 1/4 of the remaining pages of the book.He read the remaining 1/3 of the book at night. how many pages were there in the book?

Thank you v much for the effort to draw out this explanation. Appreciated! Thanks so much SahMom

[belnanna]

Please can someone solve this question with explanation not using algebra?
Would appreciate it.. Thanks so much in advance.

Nathan read 25 pages of a book in the morning.In the afternoon, he read 1/4 of the remaining pages of the book.He read the remaining 1/3 of the book at night. how many pages were there in the book?

Hi belnanna

Good Evening.

The MD may be useful to your child.

I’ve drawn more MD than necessary; students may consolidate when they become more familiar.

5u ----- 25

1u ----- 5

9u ----- 45

I’ll leave it to your child to carry on with the details.

Hope this helps.

Best wishes.

Thanks so so much Tianzhu for this post. Much appreciated for the effort. Understood now. Thanks again!