Bhal's Library Quiz
In a school library, there are 1000 boxes which are numbered from 1 to 1000. 1000 students are selected from school and they are also numbered from 1 to 1000. Initially all the boxes are open. Student no. n goes and change the configuration of every box whose number is divisible by the student's number. This process is done by all 1000 students one by one from 1 to 1000. Finally how many boxes are open?
The answer is 969.
This section requires Javascript.
You are seeing this because something didn't load right. We suggest you, (a) try
refreshing the page, (b) enabling javascript if it is disabled on your browser and,
finally, (c)
loading the
non-javascript version of this page
. We're sorry about the hassle.
1 solution
1000-floor(sqrt(1000))