Cookie Monster buys 10 boxes of cookies at an average price of $24 per box and then Buys 15 more boxes at an average price of $30 per box. What is the average (arithmetic mean) price per box that Cookie Monster paid for the 25 Boxes of cookies?
选项：

A: $26.80
B: $27.00
C: $27.20
D: $27.40
E: $27.60