Kids Riddles

Question: If 1/2 of 5 is 3, then what is 1/3 of 10?

Question: Smell me, buy me, and deliver me.
I won't change.

What am I?

Question: Without fingers, I point,
without arms, I strike,
without feet, I run.

What am I?

Question: I am the only organ that named myself.What am I?

Question: I go up and I go down,
towards the sky and the ground.
I'm present and past tense too,
Let's go for a ride, me and you.

What am I?