Yeap, thanks for your comments. I certailnly thought that it was a poorly worded sentence too. We will definitely clarify with the teacher.

Hi, dear CoffeeCat and ksi,


Indeed the last sentence sounds funny, and this is the reason we like to double check our interpretation. There are lots of solutions on the Internet that provided the same answers as yours, i.e. locker 1 and 4 are opened, 2, 3, 5 closed.

But because of the action on the last sentence, "Every student goes through, reversing the lockers which correspond to his or her position in line until the 1000th student has passed through", we felt this answer will get inverted, i.e. 2, 3, 5 Open, 1 and 4 Closed, which ksi had provided, and this was what we got also. Does this "inversion" make sense ?

Incidentally, most of the solutions on the Internet do not have this last sentence. I think the school added this sentence to introduce some variance to the question.

What do you all think ?

Hi,


Thanks for your reply. This was what we got also.

Hi, all,


This is an assignment question for my son in Sec 1. I would like to poll your understanding in interpreting this question, especially the last sentence:

Beginning of question:

Imagine a school with 1000 numbered, closed lockers, one for each of its students. Suppose all the students line up and go through the locker area to perform a specific task.

The first student will open all the locker doors.

The second student will close all the locker doors with even numbers.

The third student will change all the locker doors with numbers that are multiples of three. (Change means closing lockers that are open and opening locker doors that are closed.)

The fourth student will change the position of all the locker doors numbered with multiples of four, the fifth student will change the position of all the locker doors that are multiples of fives, and so on.

Every student goes through, reversing the lockers which correspond to his or her position in line until the 1000th student has passed through.

End of question.

To keep things short, I would like to identify the first 5 lockers' positions (whether opened or closed).

We would like to double check our understanding of the question

Thks and best rgds.