Solution to lateral thinking puzzle 1:

The man is very, very short and can only reach halfway up the elevator buttons. However, if it is raining then he will have his umbrella with him and can press the higher buttons with it.

Solution to lateral thinking puzzle 2:

The surgeon is the child's mother.

Solution to lateral thinking puzzle 3:

It's daytime.

Solution to lateral thinking puzzle 4:

At the time she went into labor, the mother of the twins was traveling by boat. The older twin, Terry, was born first early on March 1st. The boat then crossed a time zone and Kerry, the younger twin, was born on February the 28th. Therefore, the younger twin celebrates her birthday two days before her older brother.

Solution to lateral thinking puzzle 5:

This is logical rather than lateral, but it is a good puzzle that can be solved by lateral thinking techniques. It is supposedly used by a very well-known software company as an interview question for prospective employees.

A square manhole cover can be turned and dropped down the diagonal of the manhole. A round manhole cannot be dropped down the manhole. So for safety and practicality, all manhole covers should be round.

Solution to lateral thinking puzzle 6:

The poison in the punch came from the ice cubes. When the man drank the punch, the ice was fully frozen. Gradually it melted, poisoning the punch.

Solution to lateral thinking puzzle 7:

Solution to lateral thinking puzzle 8:

They were two of a set of triplets (or quadruplets, etc.). This puzzle stumps many people. They try outlandish solutions involving test-tube babies or surrogate mothers. Why does the brain search for complex solutions when there is a much simpler one available?

Solution to lateral thinking puzzle 9:

The man had hiccups. The barman recognized this from his speech and drew the gun in order to give him a shock. It worked and cured the hiccups--so the man no longer needed the water. This is a simple puzzle to state but a difficult one to solve. It is a perfect example of a seemingly irrational and incongruous situation having a simple and complete explanation. Amazingly this classic puzzle seems to work in different cultures and languages.