Answer: Scientific notation is used in the real world to make writing very large numbers, like the distance of a star from Earth or the weight of our oceans, much simpler and easier, especially when writing them in things like reports or scientific papers.
Step-by-step explanation: For example, the distance of the Sun from Neptune is somewhere around 4,500,000,000km. Writing this number takes time, and when you have to write this over and over, it wastes time, so instead, you would write 4.5 × 10⁸, which is much shorter and saves time when writing it down in a scientific report/paper many times.
Sorry for the really long explanation, I'm pretty sure just the 'Answer' bit should be fine, but you can include the 'Step-by-step explanation' bit if you want.
Hope this helps!