What does this rebus mean?

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There are 100 bulbs in a room. 100 strangers have been accumulated in the adjacent room. The first one goes and lights up every bulb. The second one goes and switches off all the even-numbered bulbs - second, fourth, sixth... and so on. The third one goes and reverses the current position of every third bulb (third, sixth, ninth? and so on.) i.e. if the bulb is lit, he switches it off and if the bulb is off, he switches it on. All the 100 strangers progress similarly.

After the last person has done what he wanted, which bulbs will be lit and which ones will be switched off?

A newspaper is supposed to have 60 pages.Pages 14 and 21 are missing from the newspaper.

Can you tell me , Which other pages won't be there as well ?

A man is surviving on an island along with his friend. They have been starving for four days for food. Suddenly, they find a fisherman. The friend goes with the fisherman in order to catch the fish (if they can find any).

The fisherman returns after some time but he is alone and has some salmon that he had prepared. When asked, the fisherman tells him that his best friend fell off the boat and drowned in the water. Starving for so long, he eats the meal while crying for his friend.

After being rescued, he goes to a diner and orders salmon. When he eats his meal, he jumps and commits suicide. Why did he do it?

Is the statement valid that it does not matter how much older a sibling is, eventually the younger one will be half as old as the older one?

I am taken from a mine and shut up in a wooden case, from which I am never released, and yet I am used by almost every person. What am I?

If two's company, and three's a crowd, then whats four and five ?

If you remove one from eleven, it becomes ten. If you remove one from nine, it becomes ten.

How is this possible?

Use only one mathematical symbol and all numbers (0-9) to get a sum of 99

Can you find out which options fits best with the missing column?