An SAT tutoring service charges a $500 fee for two sessions, plus $50 for each additional session. Emily doesn't want to spend more than $700 on tutoring. What is the maximum number of additional sessions (beyond the first two) that Emily can book for her tutoring sessions?
Let's say that Emily can book a maximum of x additional sessions.
The cost of the two sessions is $500.
The cost of each additional session is $50, so the total cost of the additional sessions is $50x.
The total cost of all the sessions, including the additional ones, is $500 + $50x.
Emily doesn't want to spend more than $700 on tutoring, so we can write the following inequality: $500 + $50x ≤ $700.
By isolating x, we have $50x ≤ $200 and dividing both sides by $50, we get x ≤ 4.
Therefore, the maximum number of additional sessions that Emily can book is 4. Answer: \boxed{4}.