A company charges $7 for a T-shirt and ships any order for $22. A school principal ordered a number of T-shirts for the school store. The total cost of the order was $1,520. How many T-shirts did the principal order?
Let the number of T-shirts ordered be x.
The cost of the T-shirts is 7x.
The total cost of the order is 7x + 22 = 1520.
Subtracting 22 from each side of the equation, we get 7x = 1498.
Dividing both sides of the equation by 7, we get x = <<214=214>>214.
The principal ordered 214 T-shirts. Answer: \boxed{214}.