Q&A - P5 Math

[Xiao Hu]

tianzhu:

sokk:

Hi,


Have a question on average that I need help with. Thanks !

Bin has $30 more than Ron.
Wei has 4/3 of the average of what Ron and Bin have.
The average amount that Bin and Wei have is 1.5 of Ron's money.
How much money does Wei have?

Thanks !

Hi

You may work using MD or units.

Ron ----- 6 units

Bin ----- 6 units + 30

Average of Ron and Bin ----- 6 units + 15

Wei has 4/3 of the average of what Ron and Bin have.

Hence, Wei ----- 8 units + 20

Total amount of Bin and Wei ----- 14 units + 50 (6 units + 30 + 8 units + 20)

Average of Bin and Wei ----- 7 units + 25

1.5 of Ron’s money ------ 9 units (1.5*6)

7 units + 25 ----- 9 units

1 unit ----- 12.5

Wei ----- 8*12.5 + 20 ----- 120

Best wishes

Hi Tianzhu,
Hope you could let us know how you've come to assign 6u to Ron (Ron ----- 6 units). That seems to eventually help to give nice whole round number later on when it comes to getting the average (Average of Bin and Wei ----- 7 units + 25).

Thanks in advance,
Xiaohu

[tianzhu]

Xiao Hu:

Hi Tianzhu,
Hope you could let us know how you've come to assign 6u to Ron (Ron ----- 6 units). That seems to eventually help to give nice whole round number later on when it comes to getting the average (Average of Bin and Wei ----- 7 units + 25).

Thanks in advance,
Xiaohu

Hi Xiaohu

I’d like to work with whole unit rather than partial form.

You may also use Ron ----- 3 units, the final answer still remains the same.

Best wishes

[Oracle]

Hi Tianzhu,

I am not a newbie just that I haven’t been active for a while until now. See that you have been helping other like-minded parents with some of the problematic math questions, I decide to consult you. Have been racking my brain over two P5 math questions since last night and still unable to come to any satisfactory answer. Am hoping that you could help:
(1a) In a cookie eating competition, Aisha ate four times as many cookies as Bee Yian and thrice as many as Celine. If Aisha ate 88 more cookies than Celine in the competition, how many cookies did Aisha eat in the competition?
(1b) In a cookie eating competition, Aisha ate twice as many cookies as Bee Yian and thrice as many as Celine. If the 3 of them ate 88 cookies in the competition, how many cookies did Aisha eat in the competition?
Thanks a million!!

[tianzhu]

Oracle:

(1a) In a cookie eating competition, Aisha ate four times as many cookies as Bee Yian and thrice as many as Celine. If Aisha ate 88 more cookies than Celine in the competition, how many cookies did Aisha eat in the competition?

Hi

Hope this helps.

Best wishes

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[tianzhu]

Oracle:

(1b) In a cookie eating competition, Aisha ate twice as many cookies as Bee Yian and thrice as many as Celine. If the 3 of them ate 88 cookies in the competition, how many cookies did Aisha eat in the competition?

Hi

Aisha ----- 6 units

Bee Yian ----- 3 units

Celine ----- 2 units

11 units ------ 88

1 unit ----- 8

Aisha ------ 6*8 ------ 48 cookies

Hope this helps.

Best wishes

[Oracle]

Wow! Tianzhu. Thanks!

[hazelwong]

quekcc:

hazelwong:

Hi, please help:

Lili and Jane shared a total of 88 stamps. Lili gave half her stamps to Jane. Jane in turn gave half her stamps to Lili. In the end, Lili had 40 stamps more than Jane. How many stamps did Lili have at first?
TIA

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:thankyou:

[Oracle]

Tianzhu, how should I approach a question such as:


Estimate the value of 7512 + 3281

Do I round off to the nearest tenth, hundredth or thousandth?

Thank you very much.

[Jamesbond]

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Pl help me solve (b) & (c).

[Jamesbond]

Oracle:

Tianzhu, how should I approach a question such as:


Estimate the value of 7512 + 3281

Do I round off to the nearest tenth, hundredth or thousandth?

Thank you very much.

Think question should be Do I round off to the nearest tens, hundreds or thousands...(not a decimal)
In that case it should be rounded off to thousands.