On a Saturday night, each of the rooms at a certain motel was rented for either $50 or $60. If 10 of the rooms that were rented for $60 had instead been rented for $50, then the total rent the motel charged for that night would have been reduced by 25 percent. What was the total rent the motel actually charged for that night ? Select the correct option
A) $ 400
B) $ 800
C) $ 1,000
D) $ 1,600
E) $ 2,400

Rationale: let total rent the motel charge for all rooms = x if 10 rooms that were rented for 60 $ had instead been rented for 50 $ , then total difference in prices = 10 $ * 10 = 100 $ total rent the motel charged would have been reduced by 25 % . 25 x = 100 = > x = 400 answer a
Answer: A