The given error is the error of concept as Chhaya does not know that two negatives cancel out each other.
CTET Solved Paper MCQ - CTET September 2015
At the upper primary stages, focus is laid on the organisation and interpretation of collected data.
There are numerous approaches to solve math problems, which includes drawing a picture, questions and check, work backwards, systematic listing and logical reasoning. Mathematics is not a subject of rote learning. It is rather a subject of conceptual understanding.
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According to Piaget, when the child is at formal operational stage, it is appropriate to introduce
According to Piaget, when the child is at formal operational stage, it is appropriate to introduce ratio and proportion as at this point of development, thinking becomes much more sophisticated and advanced.
Interdisciplinary approach gives practical shape to the knowledge of various subject. So, the given problem is interdisciplinary in nature.

