50 is even number
Sum of any even number is even
Sum of one odd number and one even number is odd number
Sum of two odd number is even number
So
If you sum odd numbers of odd number you will odd number
Example 1+3+7=11
Here the sum of three odd numbers (1,3,7) is also a odd number (11)
Similarly if you sum up 9 odd numbers you will get odd number but 50 is even number so it is not possible