Similarities:
1, the relationship between things has two variables, one is quantitative.
2. Among these two variables, when one variable changes, the other variable will also change.
3. The product or quotient of the corresponding two variables is certain.
Mutual transformation:
When the value of x in inverse proportion (the value of independent variable) is also transformed into its reciprocal, it is transformed from inverse proportion to positive proportion; When the value of x in a positive proportion (the value of independent variable) is transformed into its reciprocal, it is transformed from a positive proportion to an inverse proportion.