Question
Question: The number of ways in which we can post 5 letters in 10 letter boxes is...
The number of ways in which we can post 5 letters in 10 letter boxes is
A
50
B
510
C
105
D
None of these
Answer
105
Explanation
Solution
We can post the first letter in 10 ways, the second letter in 10 ways and so on. Thus, the number of ways of posting 5 letters in 10 letter boxes is 10 x 10 x 10 x 10 x 10 = 105