Q&A - PSLE Math

[Belle2011]

tianzhu:

Hi


As in any questions on areas of circles, it’s helpful to arrange the figures. In this question, once a student puts in the four small squares of 10cm side, the answer becomes clear.

You may choose to work with four small squares and a circle of 10cm radius or two small squares and a semi circle of radius 10 cm.

Hope this helps.

Best wishes.

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Dear tianzhu,
Amazing!
Thank-you for your solution.

Cheers,
Belle.

[match3frog]

Hi, need help with this question:


Isaac was reading a book. On the first day, the number of pages he read was 2/5 of the number of pages unread. On the second day, he read another 24 pages of the book. As a result, the number of pages he read was 5/9 of the number of pages unread. If he had to complete reading the book in another 4 days, what was the average number of pages he had to read a day for the rest of the book?

Thanks!

[ozora]

thanks lizawa and yuxuan

[small]

match3frog:

Hi, need help with this question:


Isaac was reading a book. On the first day, the number of pages he read was 2/5 of the number of pages unread. On the second day, he read another 24 pages of the book. As a result, the number of pages he read was 5/9 of the number of pages unread. If he had to complete reading the book in another 4 days, what was the average number of pages he had to read a day for the rest of the book?

Thanks!

Hi,

Hope this helps. The answer is 56 pages.

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[tianzhu]

Belle2011:

Dear tianzhu,

Amazing!
Thank-you for your solution.
Cheers,
Belle.

Hi Belle2011

Good Morning.

You're welcome.

Best wishes

[Yu Xuan]

match3frog:

Hi, need help with this question:


Isaac was reading a book. On the first day, the number of pages he read was 2/5 of the number of pages unread. On the second day, he read another 24 pages of the book. As a result, the number of pages he read was 5/9 of the number of pages unread. If he had to complete reading the book in another 4 days, what was the average number of pages he had to read a day for the rest of the book?

Thanks!

My first reply seems to have gotten lost...

1st Day
Read : Not Read
2 : 5
4 : 10

2nd Day
Read : Not Read
5 : 9

(Equate the total of both days since total number of pages should be the same.)

5units - 4 units --> 24
9 units --> 24 x 9 = 216
216 ÷ 4 = 54

[small]

Many apologies for my wrong answer, Yu Xuan’s answer is correct.


I read the question wrongly in this morning, sorry.

[teddy7171]

Plz help.


Mrs Tan bought 4 times as many toy guns as teddy bears. She spent $1750 altogether. A toy gun cost $10 less than a teddy bears. The total cost of Toy guns was $490 more than the total cost of teddy bears.
i) how much did Mrs Tan spend on the teddy bears?
ii) how much did one teddy bear cost?

Thanks.

[tianzhu]

teddy7171:

Plz help.


Mrs Tan bought 4 times as many toy guns as teddy bears. She spent $1750 altogether. A toy gun cost $10 less than a teddy bears. The total cost of Toy guns was $490 more than the total cost of teddy bears.
i) how much did Mrs Tan spend on the teddy bears?
ii) how much did one teddy bear cost?

Thanks.

Hi

A quick answer.

Cost of Teddy bears ------ (1750 - 490) / 2 ------ 630

Cost of Toy guns ------ 1120


Toy guns ------ 4units

Teddy bears ------ 1unit

Cost of 1unit of Toy guns ------- 1120 / 4 ------ 280

Cost of 1unit of Teddy bears ------- 630

630 - 280 ------- 350

Difference in cost between 1 TG and 1 TB ------- 10

Number of Teddy Bears ------ 350/10 ------- 35

Cost per Teddy bear ------- 630 / 35 ------ 18

Best wishes

[Neat]

tianzhu:

small:

Thank you very much Tianzhu. :salute: :salute:
My son's answer is 107 and the given answer was 131, so better to get some advice from here.
:celebrate: :celebrate:

Hi small

You're welcome.

As shown in the earlier post,there are multiple answers to your question.
107 is one of them.There are three more possible answers, 119, 131 and 143.

Best wishes

[quote] Hi Tianzhu,

I would like to know how to jump to know that 104 is multiplier of 4?

Regards

Neat[/quote]