This common questions is asked by students who need a reason to study mathematics. I can point to a chart on the wall, answer it with examples but they still just shake their heads and tell me they are never going to need it. I stumbled across a lovely website called Appreciate Math which gives some nice real life examples. There are not too many examples but it looks like the site author recently started. The entry on Math in Nature has a short 2:44 video I can show my students to give them a chance to see mathematics in real life. I may even take the entries and have my students read and summarize the material as a way of helping answer that question and to get them to practice their reading and writing skills.
Most of my students see reading and writing as something that only happens in English or Social Studies. As a school we are trying to increase test scores by increasing reading and writing across the core subjects.