Test your children’s problem-solving skills – and your own – with this new weekly series of maths questions presented by Marshall Cavendish Education.
The series will feature a new question each week. The worked solution for that question will be published online at http://str.sg/4eEy on the same day, and in print the following week.
To start off the series, we have provided one question and its solution, as well as a second question to keep your brain juices flowing.
The questions are targeted at students in upper primary, and the worked solutions have been given by Assistant Professor Dr Lee Ngan Hoe, Assistant Head (Mathematics Education – Teaching) of the Mathematics & Mathematics Education Academic Group from the National Institute of Education (NIE) at Nanyang Technological University (NTU). Dr Lee is also the co-author of Shaping Maths and Maths Works!
Advice for students
1. Try to understand the question first. What is the problem about? What information has been given? What does it mean? What are you supposed to find?
What happens to a number when its decimal point is shifted to the right by one place? What does it mean to say “the difference between the original number and this new number is 7.29”?
2. Work out a plan to solve the problem. What could you try to do?
How could you represent the information? Are there relationships among the pieces of information contained in the problem?
3. Try to make sense of the answer. How comfortable are you with your answer? Is there a way to check it? What have you learnt from solving this problem?
Be systematic when solving an unfamiliar problem. Do not focus too much on whether you can get the answer.
Try to understand the problem and draw on your mathematics knowledge to make sense of it. It is helpful to represent a problem in diagrams to look for relationships.
Avoid being too quick to accept an answer to a problem. Try to see if the answer makes sense and find a way to check your answer.
Advice for parents
1. Be a partner along this problem-solving journey. For some children, solving such unfamiliar problems may be a rather challenging experience and it is reassuring to have a loved one on the journey. Do not be too anxious to lead as that may block the child's view. Encourage the child and give him or her a helpful tug along the way.
2. Discourage the child from making pre-emptive judgements on whether he or she can solve the problem. Encourage him or her to make sense of the problem instead. Ask the child questions about the context of the problem to help him or her understand it. Act out how you would attempt to solve the problem. Sometimes your experience is the best teacher for the child.
3. Help the child activate the necessary maths knowledge and skills to solve the problem. Encourage the child to look for familiar words in the problem context which might trigger the necessary skills. It would also serve the child well to continuously revisit his or her mathematical knowledge and skills Maths skills needed for this problem include decimals and place values, multiplying numbers with decimals by 10, and dividing numbers with decimals by a single-digit number.
4. Children may be hasty in accepting an answer, especially if the journey has been challenging. Encourage children to check the steps in their work and also to make sense of their final answer.
Brought to you by Marshall Cavendish Education