What will come in place of the question mark (?) in the given number series? 721, 361, 181, 91, 46, ?

Explanation

The pattern is : 721 $$- 360$$ = 361 361 $$ - \frac{360}{2} = 361 - 180$$ = 181 181 $$ - \frac{180}{2} = 181 - 90$$ = 91 91 $$ - \frac{90}{2} = 91 - 45$$ = 46 46 $$ - \frac{45}{2} = 46 - 22.5$$ = 23.5