VietNamNet Bridge – A simple math question given to primary school students has led to a debate among parents, teachers and scholars.

The math question, posted by a parent on an education forum, is as follows: there are four coops in Lan’s house, and there are eight chickens in every coop. How many chickens does Lan have in total?

There were four options for the answer: A. 4x8=32  B. 8x4=32  C. 4+8=12  D. 8:4=2

The parent said his daughter chose A. 4x8=32. However, the teacher told her that this was wrong and the right answer was B. 8x4=32.

However, the parent said the teacher had been unfair as there is no difference between A and B answers, and that A is exactly the same as B, in accordance with the commutative principle (a x b is the same as b x a).

"However, Dr. Vu Thu Huong, a lecturer at the Primary Education Faculty of the Hanoi University of Education, pointed out that though both A and B give the same result, there is a difference in the meaning of the two operations

“As students are asked to calculate the number of chickens Lan has, the right answer must be B, or 8 chickens x 4 coops =32 chickens,” she said.

“If A is chosen, this should be understood as 4 coops x 8 = 32 coops,” she explained,

“As for parents, who know the commutative principle, both 4x8 and 8x4 will produce the same result. However, primary school students do not know this principle. Therefore, if the figures are put in the wrong order, students will misunderstand the matter.”

The educator went on to say that parents should think carefully before raising their voice to criticize primary school teachers.

“They (the teachers) have their reasons when asking students to follow the rules. It is necessary to go step by step when teaching students; you cannot teach them everything at once,” she said.

However, an algebra expert, who requested anonymity, said the argument by the lecturer of the Hanoi Education University has “given me a start”.

“The way the primary school teachers ask students to follow will create an odd scientific language,” he said in an interview with VietNamNet.

“According to international practice, 8 chickens + 8 chickens + 8 chickens + 8 chickens = 4 times 8 = 4x8 = 32 chickens,” he said.

“In all the math books published in the world, you will see that a + a +…+ a (100 times)  will mean 100a, not a100,” he explained. “This means that if 8+8+8+8, this must be 4x8, not 8x4”.

“It is really dangerous to teach students that way. The Ministry of Education and Training needs to be aware of the problem and adjust the teaching method as soon as possible,” he said.

The expert said he can see the same mistake in many other math lessons. In a lesson about perimeter of a square, students are asked to calculate the perimeter of a square with the square’s side equal to “a”. The perimeter must be “4a”, while it was written as “ax4” in the book.

Van Chung