How will you measure 15 minutes using two hourglasses of 7 minutes and 11 minutes respectively?

A high school has a strange principal. On the first day, he has his students perform an odd opening day ceremony:

There are one thousand lockers and one thousand students in the school. The principal asks the first student to go to every locker and open it. Then he has the second student go to every second locker and close it. The third goes to every third locker and, if it is closed, he opens it, and if it is open, he closes it. The fourth student does this to every fourth locker, and so on. After the process is completed with the thousandth student, how many lockers are open?

A spy was in Canada trying to steal insider information on how to set up new Maple Syrup factories in their country. He was introduced to the operations manager of the biggest factory in Canada. However, the manager was suspicious and decided to test him with a question before he trusted him. So he asked, “What would you be sure to find in the middle of Toronto?” The spy thought fast and came up with an answer for the manager. What was his answer?

John and Jacob are planning on a vacation. John says, "It will be better if we take the train to the hotel. We will reach faster."
To this, Jacob says, "No. You are wrong. The train stops halfway to the hotel and then we will have to walk the rest of the way. We should take the bikes to the hotel directly."
John says, "You are wrong."

Now, John takes the train while Jacob takes the bike. The train travels at four times the speed of the bike. The bike travels at twice the speed of walking.

Who do you think will reach the hotel first?

You can find two rows in the given picture each with six letters. You have to unscramble the letters and make two words (one from the first row and the second from the second row). After that, you have to unscramble the circled letter as well to find a meaningful word. Can you do it?

A large water tank has two inlet pipes (a large one and a small one) and one outlet pipe. It takes 3 hours to fill the tank with the large inlet pipe. On the other hand, it takes 6 hours to fill the tank with the small inlet pipe. The outlet pipe allows the full tank to be emptied in 9 hours.

What fraction of the tank (initially empty) will be filled in 0.64 hours if all three pipes are in operation? Give your answer to two decimal places (e.g., 0.25, 0.5, or 0.75).

Different lights make me strange by changing me into different sizes. What am I?

Andrew’s doctor gives him three pills and tells him to take one every half hour. How much time will have passed by the time Andrew’s taken all three pills?

John went to meet his friend Jacob, but when he was about to reach the main gate, John notices that Jacob had a mighty dog who was fastened to the tree. The chain is long enough that it allows the dog to reach the main gate.

How can the John reach the main gate?

Readers with excellent visual skills can find three differences between the pictures of a rabbit and a fox in 11 seconds. Can you? Test your attentiveness now!