In a football championship, 153 matches were played. Every team played one match with each other. The number of teams participating in the championship is
A.  17 
B.  18 
C.  9 
D.  none of these 
Option: B Explanation : Click on Discuss to view users comments. 
Three persons enter a railway compartment. If there are 5 seats vacant, in how many ways can they take these seats?
A.  60 
B.  20 
C.  15 
D.  125 
Option: A Explanation : Click on Discuss to view users comments. Mahender said: (12:47am on Wednesday 9th December 2015)
5p3=5!/2!=5*4*3*2!/2!=60

Number n of license plates that can be made where each plate contains two distinct letters followed by three different digits is
A.  486000 
B.  468000 
C.  498000 
D.  489000 
Option: B Explanation :
n = 26 x 25 x 10 x 9 x 8 = 468000. Click on Discuss to view users comments. 