Simplify the following text for a Grade 10 native English-speaking person.
Original: The conjecture taunted mathematicians for over three centuries before Andrew Wiles , a Princeton University research mathematician , finally proved it in 1995 , and now it may properly be called a theorem .
Simplified: The conjecture challenged mathematicians for over three centuries before a British mathematician Andrew Wiles could finally prove it in 1993 . Now it is properly called a theorem .