Just read them in order, or you can read that ten plus thirty equals forty.

The difference between mathematics reading and writing: different meanings. Mathematics reading is to capitalize numbers in the process of writing, such as capitalizing one, two and three. For example: 12, pronunciation: twelve. Mathematical writing is to use lowercase Arabic numerals in the process of writing, such as lowercase 1, 2, 3 and so on. For example: 12, writing:12; It's written differently Mathematics reading is written as "capital figures"; Math writing is "lowercase numbers (Arabic numerals)".