24 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?
Choose the correct choice from the following options.
A) None of these  B) 552  C) 512  D) 524  E) 542
Explanation :   He can go in any bus out of the 24 buses.   Hence He can go in 24 ways.   Since he can not come back in the same bus that he used for travelling,   He can return in 23 ways.   Total number of ways = 24x 23 = 552. Answer : Option 552
<result>B</result>
24 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?