What is the next number in the series?

15 29 56 108 208 ?

John killed hundreds of people mercilessly and yet the police were not able to put her behind the bars. Why?

Can you count the number of squares in the given picture?

If,
29 - 1 = 30
9 - 1 = 10
14 - 1 = 15

Based on similar logic, Can you prove that the below algebraic equation is true?
11 - 1 = 10 ?

What is the fewest number of coins that would be required in order to make sure each and every coin touches exactly three other coins?

What does this rebus means ?

John named his first son Alpha, second Beta, third Charlie and fourth Delta. What is the fifth son's name?

An octopus has 8 legs. A hippogriff has 6 legs and 2 pairs of wings. A sphinx has 6 legs and one pair of wings. Now we have all 3 kinds and a total of 18 insects in a cage. We have a total of 118 legs and 20 pairs of wings. How many insects do we have of each kind?

What occurs twice in a week, once in a year but never in a day?

A girl says this to her best friend: “I was born in 1955, and I celebrated my 17th birthday last weekend.” Her best friend thinks she’s lying, but she’s actually correct. How is that possible?