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Difficult problems in primary school mathematics
Two years ago:

2*2=4

2*9= 18

18-4= 14

Three years later:

3*2=6

6+7= 13

3*7=2 1

2 1- 13=8

Two years ago was twice as much as three years later.

8+ 14=22

22/2= 1 1

A: Xiao Li is 1 1 year old this year.

Explanation:

Two years ago, my parents lost two years each, so they lost four years.

Xiao Li is also reduced by 2 years, which is 9 times that of 2 18. Therefore, the age of parents plus 14 years old is nine times that of Xiao Li this year.

After three years, my parents increased by three years each, so they increased by six years. Seven years younger, so add 7 13.

Xiao Li has also grown by three years, which is seven times that of 32 1. Xiao Li's age is 7 times 2 1, and his parents' age is 13. 2 1 subtract 13 to get 8. Therefore, it can be concluded that small 8's parents are seven times as old as Xiao Li's this year.

Therefore, twice the age of Xiao Li this year is exactly equal to 14+8=22, and Xiao Li is 1 1 this year.