Two more new books published on amazon.com

In today’s world, they still solve math problems manually, each with some assumptions being specific numbers.
Example: Both chickens and dogs 36. Bundle to round 100 even legs. How many chickens and dogs are there?

They found some solutions using temporary assumptions for Primary School, another solution is to make an equation or a system of equations. . . They think it’s creative. Just that !

Why not change the number 36 is a positive integer a , the number 100 is a number
b is a positive integer and gets a lot of dynamic results
These problems are mentioned in detail in the book of author Le Manh Dung: