You walk into a room where there are three primates held in their respective cages:
1) A lion who is eating the flesh of a goat.
2) An orangutan who is playing with blocks.
3) A donkey who is sitting idle.

Who is the most intelligent primate in the room?

You can hear me, but you can't touch or see me.

What am I?

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?

10+10 and 11+11 can give you the same answer.

Explain how?

John can place six large boxes or nine small boxes into a carton.

Can you find out in how many cartons can he place sixty-six boxes in total?

A certain street contains 100 buildings. They are numbered from 1 to 100. How many 9's are used in these numbers?

Always in you, Sometimes on you;

If I surround you, I can kill you.

What am I?

Can you replace the X (both small and big x) with the numbers between 1 to 19 such that all the rows of 3 numbers between X (big x) sum to 23?

I guess 76.8% of readers will like this riddle.

What's the least number of people should read this post?

Can you find the next number in the below sequence
3 , 7 , 10 , 11 , 12 , 17 ?