Answer:
student's age = x years.
Teacher's age = 2x + 6
Principal's age = 3x + 10
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Difference between ages ,
[tex]\bold{(3x + 10) - (2x + 6)} \\\bold{ = > 3x + 10 - 2x - 6} \\ \bold{= > x + 4}[/tex]
therefore ,
second option is the correct answer.
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