Dan arranges two rows of pennies so they are equal in length. a child views the rows and states that they have the same amount of pennies. dan then spreads out the pennies in the bottom row so that it is longer than the top one. the child now states that the bottom row has more pennies. this child is in piaget's stage of development.

This child is in Piaget's preoperational stage of development. The Preoperational stage of development described by Jean Piaget ranges from 2 to 7 years and is characterized by an increase in representative knowledge, language development, and an accelerated learning process. Understanding the conservation of matter is part of the operational stage, which will take between 8 and 11 years.

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