Gilbert notices that his sausage is sliced into six pieces, whereas his brother's is sliced into nine pieces. he understands, however, that his brother's sausage is not actually any larger than his own. this indicates that gilbert has by now reached the stage of development.

Concrete operational

Explanation: Concrete operational stage of children development system is defined as level where the children starts to think in a logical manner. The application of the logical as well as operational thinking is done on the objects only.

This stage usually occurs at age from 7 years to 11 years. This mature thinking ability of children can be operational but not hypothetical,thus it is considered to be concrete .

Gilbert is also at concrete operation stage and so understands the situation that the size of sausage is equal ,just the pieces of sausage is cut more for his brother than him.

answer; standardization;