How many members in a Swim Club? 30:70

**Thirty percent of the members of a swim club have passed the lifesaving test. Among the member who have NOT passed the test, 12 have taken the preparatory course and the 30 have not have not taken the course. How many members are there in the swim club?**

Now I did this and came up with 60 members. 70% of the club members = 42 ...so I wanted to find out 30% of 42 to get how many people have passed which I came up with 3:7 * 42 = 18...then add the totals 18+42= 60. But that doesn't seem right. 70% of 60 does not equal 42. Please help. Am I doing this right?