Primary school students' second-grade math problem children are 4 years old this year, and their mothers are 28 years old. In a few years, their mother will be four times older than their children. How to explain it? Solve with the arithmetic method of grade two;

The mother is (28-4) years older than the child (because the child grows up, so does the mother, and the mother is always 24 years older than the child).

A few years later, the mother is four times older than the child, that is, the mother is (3- 1) times older than the child.

The redundant age of the mother to the child/the redundant multiple of the mother to the child = the age of the child.

(28-4)÷(4- 1)=8 (years old)

8-4=4 (year)

In other words, when the child is 8 years old in four years, the mother will be four times as old as the child.

Checking calculation: In another 4 years, the mother is 32 years old and the child is 8 years old.

32÷8=4, the age of the mother is four times that of the child.

The formula for solving such problems is as follows:

(adult age-child age) ÷ (multiple-1)= the age of the child in that year.