1 grade for help. About the knowledge of mathematics and coins in the first grade, ten yuan, MINUS seven yuan and sixty cents, how to say it in plain words? The answer is equal to two yuan and forty cents. I think it can be understood that analogy concept. For example, there are ten watermelons now, and each watermelon can only be divided into ten parts. Now there are ten watermelons, which is equivalent to ten dollars. Now it needs seven dollars and sixty cents, which is equivalent to someone needing seven watermelons and six petals. Then give this man a watermelon, six watermelons, and how many watermelons are left? Then you can easily figure out that there are two watermelons and four watermelons left, that is, two pieces and four corners. The detailed answer is shown in the picture, and it is not easy to ask questions and want to write satisfactorily.