
Carl K. answered 02/17/20
MD, Assistant Professor of Family Medicine
Make a diagram with three mutually intersecting circles. It's impossible to do here.
Look at the clues in reverse order
The intersection of the 3 circles are 8 students taking all 3.
15 are taking German and Italian, including the 8 who are also taking French. So 7 students are taking German and Italian, but not French.
25 are taking French and Italian, including the 8 who are taking all 3. That leaves 17 who are taking only French and Italian.
20 are taking French and German, including the 8 who are also taking Italian, leaving 12 who are taking only French and German.
42 are taking Italian, including 8 taking all 3, and 7 taking German as well, and 17 taking French and Italian. That leaves 10 who are only taking Italian.
45 are taking German, including 8 all 3, 12 F&G, and 7 G&I, leaving 18 taking German alone.
65 are taking French, including 8 all 3, 17 F&I, and 12 F&G, leaving 28 taking French alone.
The total # of students is 100, assuming I have no typos.
28 F only
12 F&G only
18 G only
7 G&I only
10 I only
17 F&I only
8 all 3 languages.