How many different ways can a family of four sit at a rectangular dinner table with one person at each side?
a. 4 ways
b. 12 ways
c. 16 ways
d. 24 ways

Use the fundamental principle of counting. In the first seat, we can choose the seater from the four persons. On the next seat, only 3 people would be available. On the second, there are 2 and finally 1 to the last seat. Multiply all the possible number of seaters,
                                4 x 3 x 2 x 1 = 16
Thus, the answer is letter C.