This blog is managed by Song Hock Chye, author of Improve Your Thinking Skills in Maths (P1-P3 series), which is published and distributed by EPH.

Monday, March 17, 2008

Word gymnastics, mind bender or P6 Maths?

It appears that Primary schools are now trying to outdo each other – in the field of Mathematics. Section C P6 Maths set by schools appears to get tougher, wordier and more complex. I got a call from a student on Sunday night to help her solve the Maths problem below. She couldn’t solve it over the weekend.

The question below is about Fractions. However, note how the question was set. For a 12 year old, it takes a clear mind and a strong comprehension of the English language to be able to understand what is asked.

There were some mangoes at a fruit stall. In the morning, the number of mangoes sold was 2/5 of the number of mangoes left. In the afternoon, another 22 mangoes were sold. The total number of mangoes sold was 3 less than 9/14 of the number of mangoes the fruit stall had at first. How many mangoes were there at first?

Click on image below to enlarge

The above model is to help my students solve the question. I am not giving the rest of the solution or the answer, because the school that gave the question above, has not given its students the working or answer yet.

As such, I do not feel it is right to give a "free handout" to students under my care.


Anonymous said...

hello mr song my

Excel Eduservice said...


Teacher Corinna said...

came across this question on ur page n tried it out using a different method. Dont think its tt difficult. Derived immediately at the answer of 70 :)

Anonymous said...

teacher corinna, to you of course easy mah. to students different story wat.

Excel Eduservice said...

The point is not whether you find it easy to solve or not. The point is, are you, as a teacher or tutor, able to deliver to the student, the method as what is in taught in schools, such that they are able to solve another question of a similar kind?

There is no point if you are able to solve it, yet unable to teach the students such that, they understand how to solve the question without any help, should they come across another question of a similar kind.

After all, it must be remembered that it is not you, but the student, who will sit for the PSLE - without anyone's help.

If the teacher's or tutor's delivery is poor, the students will be left in the lurch, none the wiser.

Just to relate my experience – A few years back, my wife and I operated a centre and we employed ex-teachers. We found that while Secondary teachers were proficient in teaching secondary maths, they were totally stumped when it came to Primary PSLE maths.

It was not that they could not solve PSLE Maths. They solved the problems easily.

The problem was their delivery. They could not transfer their knowledge to the students.

Many parents, students (and even secondary teachers) do not realize that teaching secondary maths is very different from teaching PSLE Maths.

Teacher Corinna said...

Thank you for the comments. I totally agree with you that a teacher's role is certainly not simply about knowing how to solve math problems but more critically to impart the methodologies and deliver them in a way that students can comprehend easily. After all, as you put it, "it must be remembered that it is not you, but the student, who will sit for the PSLE - without anyone's help."
I have taught both weak and strong students as well as Math olympiad students. I have seen the weak ones improve from 30 range marks to scoring "A"s and ""B"s in their PSLE while the stronger ones achieve their "A*"s in their PSLE. It is certainly most rewarding as a teacher to be able to connect with the students and have students benefit and grow from our teaching.

When I gave the opinion that the question was not as difficult as was described, I was coming from a students point of view and from the relative difficulty of past questions.
I totally respect your dedication and commitment to this blog and do not doubt your expertise at what you do. However, I do not think that one may claim to be aware of all the different kinds of methodology there is to help a student with and I am certainly not talking about the secondary algebra method. I stand by the conviction to impart to students the simplest technique in a structured, systematic way which students can understand best. Ideally by teaching the model approach way u demonstrated, students can "understand how to solve the question without any help, should they come across another question of a similar kind." However, realistically, it may not be so. I don't think a teacher can say for sure that a student wont be stumped when faced with a similar question. Besides, many students have problems with the model as the students have frequently commented that they are not artists and are not adept at cutting the model. Students do face problems manipulating models, even the strong ones.

Managing a tuition centre, I identify with you about your experience in hiring teachers.

"The man who can make hard things easy is the educator."

With all due respect,
Teacher Corinna

Excel Eduservice said...

Dear Teacher Corrina

Incidentally, Maths is the easiest of all PSLE subjects for teachers to work on in order to bring up grades. Getting students who score from 30+ to the “A” range is not uncommon. In fact, I wrote an article, targeted at teachers, on how to motivate a weak class, using Maths as a motivating agent. Here is that link.

How do I motivate the class? Part 1

It is true that not all students will be able to replicate what is taught by teachers. If that can be done, all students will score 100% for Maths. The heuristics method was introduced into schools about more than 10 years ago. Model drawing is one of the methods used.

Some students do not wish to draw models because it is “cumbersome”. The usual excuse given is that they are not artists.

However, in model drawing, students are advised to use a ruler and to draw each unit proportionately. My reply to such students is that there are markings with cm intervals to help them do that. Model drawing, like any other method, takes practice.

It is OK if a student does not use models. As long as the working is mathematically correct, he would be marked correct. I have also commented on that more than once as these links show –

Is there a standard template to answer Sect C Maths?

More than one way to solve Math problem sums

Algebra allowed but not encouraged

keentolearn said...

Mr Song’s blog certainly bring much joy to P5 and P6 school children, especially to those who do not have the privileges of additional tuition or enrichment classes. If I may add, it is one of the most useful site providing free resources for PSLE students.

There are many ways to arrive at a solution, depending on the preference of the individual. Some methods may be more efficient than others. Wish to appeal to those who think they may have better and more effective way to solve a problem, perhaps you may want to consider posting your methodology so that others may also benefit.

Anonymous said...

Hi, I came across your blog and i find this quite interesting.

Standing on the students' point of view, this question is not difficult at all but to put it in a simple context, this question is kind of challenging at first glance or should i just say a mind blower.

I managed to solve this question with ease and the answer to such question is 70. Let me show how i derive the answer and hope the students are abled to benefit from this.
Unfortunately, however, it is impossible to draw the model in this chat, but i will try my utmost best to derive the answers. As such, i urge the students to pay attention on this.

9 units ---- 4 small units + 22 + 3
4 small units + 25

5 units ---- 25 mangoes
1 unit ---- 5 mangoes
14 units --- 14 × 5
= 70 mangoes