Give an example of someone who has fixed mindset that could develop a growth mindset

A person who has a fixed mindset thinks that some people are born smart, and others aren't smart - such as himself. Since he can't "do math," for example, then he says to himself, "I can't do it and never will be able to; it is what it is."

A person with a growth mindset believes that we're all born at the same level of abilities. Those that appear smart in a given area such as math are smart simply because they practiced and worked hard. The person says to himself, "Anyone can master something with enough time and effort. Even I can do it."