I have no doors but I have keys, I have no rooms but I have space, you can enter but you can’t leave! What am I?

Can you find the thief by just looking at the picture below?

Find the next number in the series below

21 32 54 87 131 ?

If I remove one from eleven it becomes Ten and if I remove one from nine also becomes Ten. How?

An ape is trying to climb on a pole that is 60 feet high. Due to the slippery surface, the ape climbs 3 feet in a minute only to slip back 2 feet.

How much time do you think the monkey will take to reach the top of the pole?

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?

If you drop me I’m sure to crack, but give me a smile and I’ll always smile back. What am I?

A family is trapped in a jungle. There is a bridge which can lead them to safety. But at one time, the bridge can only allow two people to pass through. Also, all of them are afraid of the dark and thus, they can't go alone.

Father takes 1 minute to cross, the mother takes 2 minutes, the son takes 4 and the daughter takes 5 minutes. While crossing the time taken will be according to the slower one. How can they all reach the other side in the minimum possible time?

We have two identical balls in terms of diameter and weight. However, one of them is solid and the other is hollow.

Without knocking the ball, can you find the solid ball?

Spot the cat in the picture below