A teacher gave an assignment to his student and it base on subtraction. After the assignment is been marked,one of his student came back to him telling him that he had mismark his assignment.
Teacher:how come?
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3-1=2 but you wrote 0.
Student:sir,3-1=0.
Teacher:explain!!!.
Student:sir,if three birds are on the tree and you throw stone at one,there will be no bird on the tree. How come they will remain two????
Teacher: