We often use our IQ to gauge how smart we are. It certainly does have something to say about your level of intelligence but there is much more to it than that.
Think about it this way. If there is an older individual who spent the majority of his life without being able to go to school or to have the benefits of an education, he may have a low IQ. At the same time, however, he may have a degree of wisdom that is not seen by many other people.
That is because we have to deal with intelligence on a number of different levels. Of course, they all figure into our IQ but it is by no means a perfect system. Sometimes, we just have an intuition that is beyond book smarts.
Maybe that is why there are some people who are able to solve these problems and other people who are not able to figure out any of them.
Look at the questions for yourself and see how you do.