GRE Sample Test 2 Quantitative Reasoning 2

One way to attack this problem is to list ${\mathit{F}}_1$ to ${\mathit{F}}_{11}$: 10, 13, 16, 19, 22, 25, 28, 31, 34, 37, 40. Notice that ${\mathit{F}}_6$ through ${\mathit{F}}_{10}$ are included in both quantities, so focus on what’s different. Quantity A is ${\mathit{F}}_4+{\mathit{F}}_5$ and Quantity B is ${\mathit{F}}_{11}$. Quantity A is 19 + 22 = 41, and Quantity B is 40. Alternatively, you know that ${\mathit{F}}_4$ has had 3 changes from ${\mathit{F}}_1$. So, ${\mathit{F}}_4$ = ${\mathit{F}}_1$ + 3(3) = 10 + 9 = 19. ${\mathit{F}}_5$ has had 4 changes from ${\mathit{F}}_1$, so ${\mathit{F}}_5$ = ${\mathit{F}}_1$ + 3(4) = 10 + 12 = 22. ${\mathit{F}}_{11}$ has had 10 changes from ${\mathit{F}}_1$, so ${\mathit{F}}_{11}$ = ${\mathit{F}}_1$ + 3(10) = 10 + 30 = 40.