Answer:
The probability is 406/625
Step-by-step explanation:
If they are of different materials, we have the following combinations of selection;
(gold and silver) or ( silver and titanium) or (gold and titanium )
The number of earrings present is 13 + 10 + 12 = 25
Probability of selecting a gold earring is 13/25
Probability of a silver is 10/25
Probability of a titanium is 12/25
Substituting these into the probabilities, we have;
(13/25 * 10/25) + (10/25 * 12/25) + (13/25 * 12/25)
= 130/625 + 120/625 + 156/625 = 406/625