Question

In how many ways 6 bikes can be parked in 9 vacant parking slots in a row?​

Answer 1

Given:

(i) 6 bikes are to be parked in 9 vacant parking slots.

To find:

(i) The number of possible ways by which it can be done.

Solution:

6 bikes can be parked in 9 parking slots in 9C6 ways.

So, the number of possibilities = 9C6 = 84

Again, the 6 bikes can be arranged internally amongst themselves in 6! (720) ways.

So, the total number of ways = 84*720

= 60,480

In 60,480 ways, 6 bikes can be parked in 9 vacant parking slots in a row.