Why is 6 afraid of 7?

You are mixing a mixture of cement and Sand with five gallons of water. You have a garden hose giving you all the water you need. The problem is that you only have a four-gallon bucket and a seven-gallon bucket and neither has graduation marks. Find a method to measure five gallons.

How many words can a quill made with the feather of a pigeon write with a 100ml bottle of black ink?

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

Replace the letters of words with a number so that the below equation holds true

BASE +
BALL
---------
GAMES
----------

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

Explain how?

You have an empty wine bottle with a cork that has been secured at the top in a normal way. There is a metal ring inside the bottle that is suspended by a string.

How can you make the metal ring drop to the bottom if you are not allowed to touch anything - not the bottle, not the cork, not the thread and not the ring?

I know a nine-letter word having only one vowel.
Do you ?

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?

what does this picture(rebus) riddle means ?