What mathematical symbol can be put between 5 and 9, to get a number bigger than 5 and smaller than 9?

An equation has been laid down using a few matchsticks. However, as you can see, the equation is not correct. Can you correct the equation if you are allowed to add or remove 5 matchsticks?

Find the value of "?" in the ball picture Riddle below:

You need to move three matchsticks to form three squares. Can you do it?

What Time Should the last watch show in the below figure?

Can you find out a way through which you can make five squares out of the given figure by moving just six match sticks?

Four people need to cross a rickety bridge at night. Unfortunately, they have only one torch and the bridge is too dangerous to cross without one. The bridge is only strong enough to support two people at a time. Not all people take the same time to cross the bridge. Times for each person: 1 min, 2 mins, 7 mins and 10 mins. What is the shortest time needed for all four of them to cross the bridge?

There are 2 people near the river and both of them want to get on the other side. The boat can only take one of them. But they got across.
How?

There are 20 people in an empty, square room. Each person has full sight of the entire room and everyone in it without turning his head or body, or moving in any way (other than the eyes). Where can you place an apple so that all but one person can see it?

Nine marbles are arranged in the image below. Can you slide two marbles to form a square?