GRE Sample Test 5 Quantitative Reasoning 1

Plug in numbers: Let 1,200 = population of State X and 600 = population of State Y. Let the population concentration of State X = 12, and the population concentration of State Y = 4. The area of State X is thus
$\frac{\mathrm{population}}{\mathrm{area}}$ = $\frac{1200}{\mathrm{area}}$ = 12
→ area = 100.
The area of State Y is thus $\frac{\mathrm{population}}{\mathrm{area}}$ = $600\mathrm{area}$ = 4 → 150
area = 150. The ratio of the area of State X to the area of State Y is thus
$\frac{100}{150}$ = $\frac{2}{3}=0.66$