In a group of 25, 10 have studied French, 11 have studied Spanish, and 8 have not studied either. How many of these studied both French and Spanish?
Show Hint
Drawing a Venn diagram helps visualize the problem instantly. The sum of the individual groups plus the "neither" group minus the intersection must equal the total population: \(10 + 11 + 8 - x = 25 \Rightarrow 29 - x = 25 \Rightarrow x = 4\).