There are six teachers. Out of them tow are primary teacher, two are middle teachers, and two are secondary teachers. They are to stand in a row, so as the primary teachers, middle teacher, and secondary teachers area always in a set. Find the number of ways in which they can do so.

Answer

48

Explanation

There are 2 primary teachers. They can stand in a row together in 2!=2 ways.
There are 2 middle teachers. They can stand in a row together in 2!=2 ways.
There are 2 secondary teachers. They can stand in a row together in 2!=2 ways.
These three sets can be arranged in 3!=6 ways
Hence, the required number of ways `=2xx2xx2xx6=48`