Ken is able to perform mathematical operations only if he can use real objects and familiar examples in counting or working out his answers. ken is in which of piaget's stage.

Ken is in Piaget's concrete operational stage.

Explanation:

According to Piaget, the concrete operational stage begins when children are around 7 years old. In this stage, logical thought begins to develop and children become more logical, nonetheless, their thinking is still very concrete. Their problem solving abilities are still narrowed to concrete and specific things, like Ken, who is able to perform mathematical operations if he can use real objects or familiar examples.

The concrete operational stage is followed by the formal operational stage.

by using  production possibilities graph.  opportunity costs are key expenses in financial matters and are utilized as a part of registering money saving advantage investigation of a venture. such expenses, be that as it may, are not recorded in the record books but rather are perceived in basic leadership by processing the money costs and their subsequent benefit or misfortune.

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