What has many keys but can’t open a single lock?

While going to your grandmother's house, you counted Twenty houses on the right side. While returning back to your home, you counted Twenty houses on the left side.

How many houses are there between your home and your grandmother's home?

Why 1729 is a magic number? Answer Logically.

I am a normal creature, but I have five hands. I can even have more but even then I will be considered normal.

Who am I?

I am a seven-letter word but if you remove four of my letters I will have one left. What word am I?

John was piloting a plane behind a car but was never able to overtake it. Why?

Manish has to secure 40% marks to pass his B.tech final exams.
He got just 40 marks and failed by 40-marks.

What is the maximum marks?

If six children and two dogs were under an umbrella, how come none of them got wet?

What can run but never walk, have a mouth that never speaks, have a head that never weeps, and have a bed but never sleeps?

I go up and I go down.
I go up towards the beautiful sky and down toward the green ground.
I am present tense.
I am past tense too
Children love me.

Who Am I?