### I need to review Venn Diagrams

Posted:

**May 19th, 2013, 10:22 pm**Hello,

I'm preparing for GMAT and I cannot understand the topic of venn diagrams. Kindly review this question by 800score.com and help me understand it better.

If, in a certain school, 20 students study mathematics, 10 study science, and 7 study both, how many students study mathematics, science or both?

Thank you for your time!!

I'm preparing for GMAT and I cannot understand the topic of venn diagrams. Kindly review this question by 800score.com and help me understand it better.

If, in a certain school, 20 students study mathematics, 10 study science, and 7 study both, how many students study mathematics, science or both?

*[Moderator edit: Link taken out]*Thank you for your time!!