Two dice are thrown. The events $A, B$ and $C$ are as follows:
$A:$ getting an even number on the first die.
$B:$ getting an odd number on the first die.
$C:$ getting the sum of the numbers on the dice $\leq 5$.
State true or false: (give reason for your answer)
Statement: $A$ and $B$ are mutually exclusive and exhaustive.

(A) The sample space $S$ for throwing two dice contains $36$ outcomes.
$A = \{(2,1), (2,2), (2,3), (2,4), (2,5), (2,6), (4,1), (4,2), (4,3), (4,4), (4,5), (4,6), (6,1), (6,2), (6,3), (6,4), (6,5), (6,6)\}$
$B = \{(1,1), (1,2), (1,3), (1,4), (1,5), (1,6), (3,1), (3,2), (3,3), (3,4), (3,5), (3,6), (5,1), (5,2), (5,3), (5,4), (5,5), (5,6)\}$
Two events are mutually exclusive if $A \cap B = \phi$. Here,$A$ contains only even numbers on the first die and $B$ contains only odd numbers on the first die,so $A \cap B = \phi$.
Two events are exhaustive if $A \cup B = S$. Since every outcome in $S$ has either an even or an odd number on the first die,$A \cup B = S$.
Therefore,the statement is true.