Question:
From among the 36 teachers in a school, one principal and one viceprincipal are to be appointed. In how many ways can this be done?
Solution:
Given: 36 teachers are there in a school.
To find: Number of ways in which one principal and one vice-principal can be appointed.
There are 36 options of appointing principal and 35 option of appointing vice-principal since same teacher cannot be appointed as principal and vice-principal.
Total number of ways $=36 \times 35=1260$