Question

How many word can be performed by word "o,r,a,n,c"?

Answer 1

5 word ...............

Answer 2

Letters are given : o , r , a , n , c
there are five latters by which we have to form words.

word seems like : ___, ___, ___, ____, ___.
now, if we start to place the latter in first blank, we can choose anyone among all five latters .
e.g., number of ways to choose first blank= 5

now , remaining four latters,
2nd blank can be filled anyone among all four latters
so, number of ways to fill 2nd blank = 4
similarly, number of ways to fill 3rd blank = 3
number of ways to fill 4th blank = 2
number of ways to fill 5th blank = 1

so, total number of ways = 5 × 4 × 3 × 2 × 1 = 120

hence, number of words can be performed = 120.