You purchased a chicken for $8 and then sold the chicken to your friend for $9. Several days later, you purchased the chicken back for $10 and then sold the chicken again to another person for $11. How much money did you earn?
Three students try to answer the question.
Student A:
You purchased a chicken for $8 and sold the chicken to your friend for $9. You first earned $1. You then purchased the chicken back for $10. So you lost $1.
You sold the chicken again for $11. You earned $1.
In total, you earned $1 - $1 + $1 = $1.
Student B:
You earned $2 because you earned $1 each time the chicken was sold.
Student C:
Your profit was -$1.