Why is the Hole below a Lock?

Do you know of a place where the wind blows south and then suddenly shifts direction towards the north?

Replace the question mark with the number below given a simple math problem.

In the formation, you can see a few arranged matchsticks. Can you form three squares by moving just three matchsticks?

Using Only Five 5's and any mathematical operator make sum as 37

A word I know has six letters it contains, remove one letter and 12 remain. What is it?

There is a square of a particular number which when doubled, becomes 7 more than its quarter.

Can you find the number?

What mathematical symbol can be put between 5 and 9, to get a number bigger than 5 and smaller than 9?

John can eat 27 chocolates in an hour, Jacob can eat 2 chocolates in 10 minutes, and Jolly can eat 7 chocolates in 20 minutes. How long will it take them to share and eat a box of 120 chocolates whilst playing Chess?

John was a very careless driver, so his owner Jacob gave him an offer that he will get an incentive of Rs.30 for every bottle box he delivered without breaking it and he will be charged Rs.90 for every bottle box he broke. Jacob gave John 100 bottles-box to deliver. After delivery, Jacob paid John Rs.2400. How many bottles-box did John break?