What has no start, end, or centre?

2, 3, 5, 9, 17, _ What is the next number in the sequence?

Can you find the missing number in the third row?
35 20 14
27 12 18
5 2 ?

How many times can you subtract the number 5 from 25?

A spaceship was lost. The detective was given a piece of paper. This was the location of the spaceship! This is what the slip had scribbled on it:
Juice, Umbrella, Potato, Ice, Tomato, Elephant, Rice.

Where is the spaceship?

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).

In 1990, a person is 15 years old. In 1995, that same person is 10 years old. How can this be?

You are given four tennis balls and asked to arrange those balls in a manner that the distance between each one of them is exactly equal. How will you do it?

Can you count the number of squares in the figure below?

Which city is three-fifths chick two third cat and 50% goat?