What comes
Once in a Year
Twice in a Month
4 times in a Week
6 times in a Day

In 1990, a person is 15 years old. In 1995, that same person is 10 years old. How can this be?

An express train takes 3 seconds to enter the tunnel which is 1 km long.
If it is travelling at 120 km an hour, how long will it take to pass completely through the tunnel?

You have two buckets of 11 liters and 6 litres.
How can you measure exactly 8 litres?

In the image given, you can find several triangles. Can you count them all?

See the given image carefully. What you have to do is move the blue checkers in the position of the black checkers and vice versa. You are only allowed to move the checker to an adjacent empty space. Do it in the least possible moves.

Take number 1000 and then add 20 to it.
Now add 1000 one more time.
Now add 30.
Now add 1000 one more time.
Now add 40.
Now add 1000 one more time.
Now add 10.

What is the total?

You have 10 balls with you. A friend of yours out of nowhere asks you to place those ten balls in five lines such that each of the lines has exactly 4 balls on them. He needs to check your intelligence. Prove him by doing the task.

People make me, save me, change me, raise me. What am I?

What does the below rebus riddle means?