18 is correct because 18x 1 =18, 1+ 1 can be said to be three1,3x/kloc. Questions like this are not difficult for the first grade of primary school. You must be able to draw inferences. If you ask, how many 2s are there in 18? For senior students, it is easy to divide 18 by 2=9, but for grade one, it can be solved by addition and subtraction.

Mathematics has been an indispensable intellectual civilization for human beings since ancient times. As a subject that studies the concepts of quantity, structure, change, space and information, everyone has a different definition of mathematics. Wittgenstein said that mathematics is all kinds of proof skills, and Russell said that mathematics is symbol plus logic. Therefore, as long as you lay a good foundation in the first grade, you can do it step by step. Here, 18 can also be said to be composed of 1 tens and 8 ones.