The replacement problem is mainly to study a typical application problem of transforming two quantities with quantitative relationship into one quantity, thus helping us find a solution. The problem of "chickens and rabbits in the same cage" is a typical replacement problem. Generally, two mathematical thinking methods, transformation and hypothesis, are used to solve the replacement problem.

Answer the replacement question should pay attention to the following two points:

1, according to the quantitative relationship, two quantities are converted into one quantity, and the solution is obtained;

2. Assuming that two quantities are one quantity, the solution can be obtained.

Hope to adopt!