1, the conversion relationship is: large company and small company: × rate (rate 10 decimal point moves one place to the right, rate 100 decimal point moves two places to the right, rate 1000 decimal point moves three places to the right, and so on).

2. Small unit and large unit: progressive rate (progressive rate 10 decimal point moves one place to the left, progressive rate 100 decimal point moves two places to the left, progressive rate 1000 decimal point moves three places to the left, and so on).