Why is 6 afraid of 7?

Can you find the key in the picture below?

I speak without a mouth, and hear without ears. I have no-body, but I come alive with the wind. What am I?

There are nine letters in the below-given diagram. You have to form a nine-letter word using these letters.

The doctor prescribed you to take one pill from the bottle every half an hour. The bottle is now left with only three pills.

How long do you think you have before you run out of pills?

1 dollar = 100 cent
= 10 cent x 10 cent
= 1/10 dollar x 1/10 dollar
= 1/100 dollar
= 1 cent

=> 1 dollar = 1 cent

solve this tricky problem?

In my garden, I have many trees but only one of them is the mango tree. In these mango trees, there are some mangoes(as expected).

But after a strong wind, there are neither mangoes on the tree nor on the ground. Explain?

What has 13 hearts but no other organs?

Always in you, Sometimes on you;

If I surround you, I can kill you.

What am I?

John left on a horse on Thursday , was gone for two days, and came back on Thursday after completing his work. How did that happen?