If two balanced dice are rolled, what is the probability that the sum of the two numbers that appear will be odd?

The sample space for the experiment has a total of 36 possibilities.

Sample space for an odd sum is { 1,2 1,4 1,6 2,1 2,3 2,5 3,2 3,4 3,6 4,1 4,3 4,5 5,2,5,4 5,6 6,1 6,3 6,5 }

Probability = 18/36 = 1/2