The number of subsets of 1,2,3, , 9 containing at least one odd number is

Step-by-step solution

The total number of subsets of given set is 2^9=512 Case I When selecting only one even number 2,4,6,8 Number of ways = ^4 C₁=4 Case II When selecting only two even numbers = ^4 C₂=6 Case III When selecting only three even numbers = ^4 C₃=4 Case IV When selecting only four even numbers = ^4 C₄=1 Required number of ways =512-(4+6+4+1)-1=496 [Here, we subtract 1 for due to the null set]