Posted by poo on .
8. In an interview of 50 math majors,
12 liked calculus and geometry
18 liked calculus but not algebra
4 liked calculus, algebra, and geometry
25 liked calculus
15 liked geometry
10 liked algebra but neither calculus nor geometry
2 liked geometry and algebra but not calculus.
Of those surveyed, how many liked calculus and algebra?

math 
PsyDAG,
If you only interviewed 50 math majors, how do you get over 80 in the various categories?
Divide the 4 that liked calculus, algebra, and geometry by whatever your total sample is.
I hope this helps.