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

Four people need to cross a rickety bridge at night. Unfortunately, they have only one torch and the bridge is too dangerous to cross without one. The bridge is only strong enough to support two people at a time. Not all people take the same time to cross the bridge. Times for each person: 1 min, 2 mins, 7 mins and 10 mins. What is the shortest time needed for all four of them to cross the bridge?

Move three sticks of the spiral below to form a square.

When it is alive we sing, when it is dead we clap our hands. What is it?

Why Wine Glass Stem is so long?

You see a mathematical expression in the picture. Can you think of a movie that this expression refers to?

The day after tomorrow will be three days before Tuesday. Can you find out what is today?

Can you find a seven digit number which describes itself. The first digit is the number of zeros in the number. The second digit is the number of ones in the number, etc. For example, in the number 21200, there are 2 zeros, 1 one, 2 twos, 0 threes and 0 fours.

I have cities, but no houses. I have mountains, but no trees. I have water, but no fish. What am I?

Below the four parts have been reorganised. The four partitions are exactly the same in both arrangements. Why is there a hole?