Answer:
The odds will be 5/13.
Explanation:
There are 13 marbles total in this situation. 5 orange, 3 yellow and 5 black (5+3+5) will give us 13 as our overall total. Now, because we have 5 orange marbles available, we'll write this as a 5/13 odds/ chance of picking an orange marbles because it is how many orange marbles are present over how many marbles there are total.
Also! You can't simplify this any further, thus you'd have 5/13 odds.