The “primary language” of mathematics

The language I use in mathematics is as follows:

Simple multiplication (e.g. “5 x 9”, “7 x 8” etc.): I always do it in Japanese. I learnt the times table in Japanese when I was in primary school in Japan, so it makes sense.

Addition/subtraction: Somehow I do it much better in Chinese, which doesn’t make perfect sense because I learnt it in Japanese. Perhaps it’s because I got a lot more intense number training while at the secondary school in China?

My “thinking language” in mathematics only became clear to me the other weekend. My husband and I were trying to see who could do multiplications of 3-digit numbers (e.g. 987 x 765) quicker on paper, which involved both multiplications and some additions. Our “competition” was intense, and I heard myself saying aloud the numbers in Japanese when I was multiplying, and in Chinese when I was adding them up!

I’ll keep silence as to whether multiplications of 3-digit numbers is a typical weekend activity that you would do with your spouse… :-)