Q&A - P3 Math

[tianzhu]

concerned1970:

Tysm Tian_zhu! It always gives me a BIG heahache when comes to Math. U're a great and wonderful dad who's willing to spend time to do the revision with yr son. Not all men like u! It's not easy.

Hi concerned1970

Good Morning.

You're welcome.

My eyes were washed with tears as I read your post.
Tears are easy to erase with tissue papers, but how do I erase the pains from my heart?

What choice do I have?

As you are aware of, Maths enrichment courses do not come cheap. I am a victim of circumstances, a \"money not enough\" dad who cannot afford my kid this avenue.

So I started to get more involved in his Maths during the second half of P5 and PSLE. At the very least, what I could offer was to help him to break down the problems into manageable steps when he encountered difficulties.

But, it’s not easy to revise with your own kid, sometimes you tend to shout at him when the going isn’t smooth. I must confess, I’ve shouted at my boy during times of frustration. Boy, daddy apologises for the unnecessary outbursts.

I wish I had deeper pockets.

世界上所有的爸爸都是一样的,they would do the same thing if given similar situation.

Best wishes

[tianzhu]

concerned1970:

Is there any other method to work out this pb sum besides guess and check method?

Hi concerned1970

Good Morning.

Yes, you can solve it in other ways besides GC.

But for P3, I think using GC with calculated guesses is quite appropriate as the numbers are not too big.

I think there are about eleven problem solving heuristics in primary maths syllabus (if I remember correctly).

If you are keen to look at alternatives, you may look at 1) Draw a diagram/picture 2) Make a Supposition, where you apply logical reasoning and 3) algebraic and solve by pictorial method.

But, I am not suggesting the third method at this moment, maybe wait until he /she is in upper primary.

Guess and Check or sometimes called Trial and Error is one of the common and simplest problem solving strategies in primary maths.

Some may say that it could take a number of guesses and is time consuming.

To use GC effectively, students need to make calculated guesses and keep a record or tabulate their trials, check their guesses against the information given in the questions and then adjust their guesses if they are wrong.

I am not a great fan of GC, I use it as a last resort. However, this method does offer a lifeline when a student runs into difficulties when experimenting with other strategies especially in examinations.

Best wishes

[tianzhu]

teh_oh:

my child (and myself) has not been exposed to such questions (to my knowledge) yet.

Hi teh_oh

These are some similar type of questions found in P3 testpapers.

The numbers are small and P3 students are usually able to solve these questions with GC without much difficulty.

1) Guo Cong Min has 12 pets which consist of birds and hamsters. All the hamsters have 36 more legs than all the birds. How many of his pets are birds?

2) Hong Yuan has a total number of 25 tricycles and bicycles in a shop. If there are 61 wheels altogether, how many tricycles are there in the shop?

3) Shu Hua has 8 coins that add up to $3.40. Some are 50¢ coins and the rest are 20¢ coins. How many 50¢ coins does Shu Hua have?

And if you are looking ahead, these are two questions from P5.You’ll see that it’s now more tedious to use GC. At upper primary level, a heuristics known as “Make a Supposition” or the “Assumption Method” is more efficient.

1)There were 50 children in Xie Ming Ming’s party. Each boy ate 10 cookies. Each girl ate 7 cookies. All the girls ate 44 more cookies than all the boys. How many more girls than boys were there?

2) Chun Hua visited a farm where she saw some ducks and goats. There were a total of 65 ducks and goats. She then counted the legs of the animals and found that there were 196 legs. How many ducks were there in the farm?

Hope this helps.

Best wishes

[tianzhu]

Hi moderator


Please help to delete duplicated post.

Thanks

Best wishes

[teh_oh]

Hi Tianzhu,


My child is in P3. His math has been his strongest subject so far as his school has yet to expose him to such challenging questions. Meanwhile, we are just maintaining once a week practices using exam papers to ensure that his foundation is strong and that he is on par with other school standards. This thread is our main source of challenging questions (with clear worked examples too! Thank you! :)) for him to practice. He challenges me to solve them as well and gets the kick of beating me to arriving at the solution. :oops:

[Champion]

teh_oh:

Hi Tianzhu,


My child is in P3. His math has been his strongest subject so far as his school has yet to expose him to such challenging questions. Meanwhile, we are just maintaining once a week practices using exam papers to ensure that his foundation is strong and that he is on par with other school standards. This thread is our main source of challenging questions (with clear worked examples too! Thank you! :)) for him to practice. He challenges me to solve them as well and gets the kick of beating me to arriving at the solution. :oops:

Hi teh_oh,
Your son is very disciplined :congrats: . My girl who is also in P3 this year is very reluctant and resistant whenever she faced challenging problem sums in the assessment books. We were working on Andrew Er's book when she gave the remarks,\" This assessment book very difficult; can give it a pass?\" :lol: Guess, I will log into this thread more often to learn more.

[teh_oh]

Champion:

teh_oh:

Hi Tianzhu,


My child is in P3. His math has been his strongest subject so far as his school has yet to expose him to such challenging questions. Meanwhile, we are just maintaining once a week practices using exam papers to ensure that his foundation is strong and that he is on par with other school standards. This thread is our main source of challenging questions (with clear worked examples too! Thank you! :)) for him to practice. He challenges me to solve them as well and gets the kick of beating me to arriving at the solution. :oops:

Hi teh_oh,
Your son is very disciplined :congrats: . My girl who is also in P3 this year is very reluctant and resistant whenever she faced challenging problem sums in the assessment books. We were working on Andrew Er's book when she gave the remarks,\" This assessment book very difficult; can give it a pass?\" :lol: Guess, I will log into this thread more often to learn more.

Hi Champion,
Thanks for the compliments.
My boy does not have any other Math assessment books as he finds that doing pages for one full topic to be very dry/tedious. He prefers doing Math exam papers which offers a 'variety' of questions from different topics. We only do a paper a week as other precious time are spent on other subjects.
Tianzhu's colourful worked solutions and the novelty of 'doing sums off the computer' which seems appealing to my child, is now my free source of 'challenging sums'.

[plum-cake]

concerned1970:

Tysm Tian_zhu! It always gives me a BIG headache when comes to Math. U're a great and wonderful dad who's willing to spend time to do the revision with yr son. Not all men like u! It's not easy.

I agree. :goodpost:

[Champion]

Hi Tianzhu & all parents,

Need your help with the following questions that DD1 came home with worksheet from school.

(1) The sum of two numbers is 7500. The greater number is twice that of the smaller number. What are the 2 numbers?

(2) Kenneth has 9 coins that add up to $2.70. Some of them are 50-cent coins and the rest are 20-cent coins. How many 50-cent coins does he have?

(3) John and Samy shared 72 sweets. John received twice as many sweets as Samy. How many sweets did John receive?

Can advise me for the above types of questions, it shall be under addition/subtraction/multiplication/division? And how to show them using models?

Sorry to trouble you all but I am at a loss when coming to Maths :imsorry:

[tianzhu]

Champion:

Hi Tianzhu & all parents,

Need your help with the following questions that DD1 came home with worksheet from school.

(1) The sum of two numbers is 7500. The greater number is twice that of the smaller number. What are the 2 numbers?

(2) Kenneth has 9 coins that add up to $2.70. Some of them are 50-cent coins and the rest are 20-cent coins. How many 50-cent coins does he have?

(3) John and Samy shared 72 sweets. John received twice as many sweets as Samy. How many sweets did John receive?

Hi Champion
I take them as P3 questions.

Q1 and Q3 are pretty similar.
You may use MD to solve them.

Big number ------ 2 units (2 rectangular blocks)
Small number -----1 unit (1 rectangular block)

3 units ------7500
1 unit ------ 2500

The two numbers are 5000 and 2500.

John ------ 2 units
Samy -----1 unit

3 units ------ 72
1 unit ------ 24

John ------ 2 units ------- 48

For Q2, a P3 student may make calculated guesses using a strategy called GC. The numbers are small and it’s not too tedious to arrive at the solution.

Or, he/she may use a heuristics known as “Draw a diagram”

In this solution, I’ll share how to solve by “Make a Supposition”. This strategy is more efficient and is used commonly in upper primary level.

Assume all were 20 cents coins.

9*20 ------ 180
270 – 180 ------90

Difference between 50 cents coin and 20 cent coin -------- 30

90/30 -------3

Hence 3 50 cents coins

Best wishes