Q&A - PSLE Math

[tianzhu]

Ler:

Hi VC and tianzhu

I try that VC given the solutions (for abc parents), but could not access to the link but only provided the solution

Sorry VC, i seldom use computer, only touches this week only, still learning, may VC can help me to link to it. for uncle observation solution. May be can type out the website for me. I saw him draw model , i seems to understand more..... thanks.

Hi Ler

Here’s Observer blog
http://prischoolmaths.blogspot.com/

This is another good resource for PSLE students
http://road-to-psle.blogspot.com/

Best wishes

[tianzhu]

kancheongmum:

Hi Tianzhu I think the original question lack some information. The student added in \"When Samad reached Town Bin 4 hours[u]\" which I didn't type. I think with that info we can solve the problem.

Hi kancheongmum

Yes, if the additional information included in the question, the answer is 10km/h for Samad.

For them to meet at 10km away from Town B, they must meet at the fifth hour.

To check, the distance between towns is 40km,Samad’s speed is 10km/h and Toy’s speed is 6km/h.

Best wishes

[tianzhu]

kancheongmum:

My lst question I try to use Sally to check if I can get the correct answer. I think I miss out something. Can I say that when Alan take 3 hours for that part of the journey, Sally will take 3 x 3/2 = 4.5 hours?
For meeting, from opposite direction, must we get the 2 to move out at the same time?

Hi kancheongmum

Yes, you are correct to say 4.5h,she took another 1.5h for the remaining part of journey making a total time of 6h.

You are also spot on in your second point.

Best wishes

[kancheongmum]

Hi Tianzhu and Dharma

Thank you got all the info now.
one more question MCQ RV2010 Q12 (ans 43 yrs old)
The average age of Mr Lim"s family of 4 is 26years old. The total age of Shawn and Mr Lim is 2 years more than the total age of Mary and Mrs Lim. How old is Mr Lim?

for algebra question if the work out answer is (168 - x)/2 + x
do the student leave the answer this way or has to simplified further to
84 + 1/2 x

[tianzhu]

kancheongmum:

one more question MCQ RV2010 Q12 (ans 43 yrs old)
The average age of Mr Lim\"s family of 4 is 26years old. The total age of Shawn and Mr Lim is 2 years more than the total age of Mary and Mrs Lim. How old is Mr Lim?

Hi

As this is an MCQ, what are the other available options?

Best wishes

[tianzhu]

kancheongmum:

for algebra question if the work out answer is (168 - x)/2 + x
do the student leave the answer this way or has to simplified further to
84 + 1/2 x

Hi

If I remember correctly, algebra is not thoroughly covered in P6.

I suggest you ask your boy to check with his teacher.

Best wishes

[Dharma]

kancheongmum:

for algebra question if the work out answer is (168 - x)/2 + x
do the student leave the answer this way or has to simplified further to
84 + 1/2 x

Hi kancheongmum,

You will need to simplify the answer to 84 + x/2

[CTong]

Pls help to solve:


James had 20 goldfishes and 30 guppies in a fish tank. 20% of the guppies died. James bought another 16 goldfishes.
a) What percentage of the fish were guppies?
b) What was the increase in percentage of goldfish?

[kancheongmum]

hi Tianzhu will ask ds to check with his teacher tomorrow.

options (1) 44 yrs old (2) 43 yrs old (3) 42 yrs old (4) 41 yrs old
tks

[Vanilla Cake]

kancheongmum:

Hi Tianzhu and Dharma

Thank you got all the info now.
one more question MCQ RV2010 Q12 (ans 43 yrs old)
The average age of Mr Lim\"s family of 4 is 26years old. The total age of Shawn and Mr Lim is 2 years more than the total age of Mary and Mrs Lim. How old is Mr Lim?

Dear Uncle Tianzhu and Uncle Dharma,

There is missing information in kancheongmum's post. There is actually a table in this question and it is stated that age of Shawn (son) -> 10 yrs old.Without this information about the age of Shawn (son), it's not possible to solve this question.

Answers option:
(1) 44 yrs old
(2) 43 yrs old
(3) 42 yrs old
(4) 41 yrs old

Suggested solution using algebra
Let the age of Mr Lim be n.
Age of Mrs Lim+Age of Mary (daughter)=10+n-2=8+n
8+n+n+10=104
2n=86
n=43

Age of Mr Lim = 43 years old
Answer option (2)