Can anyone write the procedure how to solve this below problem?
It seems we will have two answers according to the way of resolvers thinking can be thinking with Maths or with Business, please write down and share in the comment:

Problem:
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“A person bought a house for $60,000. Soon thereafter they sold it for $70,000, upon moving out of town.
A few month later, they were transftered back to town and purchased the same house for $80,000, then the person grew tired of the house and resold it for $90,000.”

Question: How much money did the person gain/lose (or break even) on the exchange? How you calculate this?