PSLE Mathematics #2

PSLE Mathematics #2 |

Durians cost $18 per kg. Find the cost of several durians that weigh a total of 5.9kg |

Together with calculations such as Find the value of 1 + 2 x 3 : 4, such one-step problems are the most basic tasks in PSLE Mathematics. Every student must be totally proficient in such tasks by the end of Primary 6. These tasks are to be done without the use of calculators.

Mental strategies are preferred - 5kg cost $50 and $40 or $90. 6kg cost $108. 0.1kg cost $1.80. $108 subtract $2 add 20 cents, for example.

More mental strategies strengthens number sense and metacognition, necessary for challenging problems.

Today's task is inspired by the durian stall near where I live. It is currently in season.

PSLE Mathematics #1

PSLE Mathematics #1 | By the end of Primary 6, students must be able to solve 2-mark problems like this ..

Kemar is 1.93 m and is 2 cm shorter than Usain. How tall is Usain? |

Students who are struggling with Maths should focus on becoming competent in basic tasks such as this one. Often you get both marks for a correct answer but an incorrect answer with a correct method such as 193+2 or 1.93+0.02. Pity students who were told look for keywords, shorter means subtract! Look out for more PSLE guidance as the national examination draws near.

Today's problem is inspired by the on-going Commonwealth Games.

Using Diagrams to Solve Problems

How many more km does Amin has to cycle to complete the race?

What if the fraction is not 1/3 ....
What if it is 1/4?
What if it is 1/5?
Can you solve the same problem i.e. to find how many more km he has to cycle to complete the race for these two new situations?

The Nature of One-Mark Questions

These are designed to find out if you know the most basic things in mathematics. These are do-able for everyone of you. If you got these wrong (one or two mistakes is okay), ask yourself what went wrong. If you cannot figure it out, ask someone.

Most of these questions are on adding, subtracting, multiplying and dividing, and sometimes in a simple story.

Can you find the values of 2000 - 489? 24.2 divided by 4? 1 half subtract 1 fifth?

The idea is not to make things too complicated because they are not.

See this for some ways of making sense of basic computation.

Find the value of 69 x 7.
Just think of doing 60 x 7 and 9 x 7. Or 70 x 7 then compensate by ...
If you still have trouble remembering the times table, look at them when your practising - after a while you will remember them. Give yourself a month of looking at them while you practise. Remember ... No calculator when you practise Paper 1.

Find the value of 12.5 - 8.07. Look at this as 12 - 8 and 50 hundredths - 7 hundredths. That way you can write down the answer straight away.

Ali paid for a 85-cent pen with a $5 note. Can you tell the change without any paper-and-pencil calculation. You should. Of the $5, put aside $4 and you will get 15 cents back from the $1.

Find the value of 3 tenths - 4 fifths.
Different types, so cannot subtract int he usual way. Get the fifths to be tenths.
4 fifths is 8 tenths. Draw a model to help you see 4 fifths is 8 tenths if you still do not know it.

For many of you these tasks are not a problem at all. Look out for advice on challenging problems in the future. For you, when you do 1- mark questions, try to do it mentally and try to get at least 9/10 for Question 1 to 10 and the same for Questions 16 to 25.

For those who did not manage at least 50 for your recent examination, keep on working on the 1- mark and 2-mark questions. Get those right and then we will work on 3-mark questions.

You will get better - just need to make sense of what you are doing.

Parents - I know you are reading this, even though it is for students, actually - what they need is a bit of guidance and a lot of assurance. If your child did not meet the C grade at this point, focus on Paper 1 for this month and June. We will get to Paper 2 once the child's confidence is there.

Help them make sense of the work they do. No short cuts. No this is the way it is done, just do it.