25 buses are running between two places P and Q. In how many ways can a person go from P to Q and return by a different bus?  Answers.
A) 625 B) 600 C) 576 D) 676 E) 700
we can go in any bus out of the 25 buses.   Hence He can go in 25 ways.   Since we can not come back in the same bus that he used for travelling,   we can return in 24 ways.   Total number of ways = 25 x 24 = 600   ANSWER:600
<result>B</result>
25 buses are running between two places P and Q. In how many ways can a person go from P to Q and return by a different bus?