How many numbers can be formed from 1, 2, 3, 4, 5, ( without repetition), when the digit at the unit's place must be greater than that in the ten's place?

How many numbers can be formed from 1, 2, 3, 4, 5, ( without repetitio

1.	How many numbers can be formed from 1, 2, 3, 4, 5, ( without repetition), when the digit at the unit's place must be greater than that in the ten's place?
A.	54
B.	60
C.	51/3
D.	2 x 4!
Answer» C. 51/3