3 : 12
Step-by-step explanation:
gold medals = 5
silver medals = 3
bronze medals = 4
total medals = 5 +3 + 4
Total = 12
ratio of silver medals to total medals = silver medals : total medals
ratio of silver medals to total medals = 3 : 12
To the lowest term:
ratio of silver medals to total medals = 1 : 4