Arihanth-Exam Articles- Logical Thinking

There are 100 bulbs and each having separate switches and on at the initial stage.
 First man enters and switches off the bulbs, which are the multiples of 2.
 Next man enters and switches on the bulbs which are off and switches off the bulbs which are on, which are multiples of 3.
 Next man does the same as above for the multiples of 4.
 Next man does it for the multiples of 5.
 This process is repeated up to the multiples of 100.
 So finally how many bulbs will be glowing.
  Rate if the question is good.

for answering and for answer go to the link below
from
http://www.goiit.com/posts/list/community-shelf-logical-thinking-1065046.htm