What always comes into a house through the keyhole?

Two boys were admitted to a school. When the headmaster asks them about their parents, they tell him that they have same parents (father and mother). On further inquiry, it turns out that they both share the same date for their birthday.

"Are you twins," ask the headmaster.
"No," replies the boys.

Is it possible?

Can you count the number of triangles in the given figure?

What has hands, but can’t clap?

There is a bag which have 21 blue balls and 23 red balls. You also have 22 red balls outside the bag. Randomly remove two balls from the bag. * If they are of different colors, put the blue one back in the bag. * If they are the same colour, take them out and put a red ball back in the bag. Repeat this until only one ball remains in the bag. What is the color of the sole ball left in the bag ?

What Does this text mean:

important=important

Find The Next Number In The Sequence

30 10 15 13 0 16 -15 ?

Find the next number in the series

12, 20, 40, 72, 116, 172 ?

What is more useful when it is broken?

2 ladies and 2 girls need to cross a river in a boat big enough for 1 LADY or 2 girls. How do they do it?