VIAMC 2025 Mock Test — Level 6 (Senior) Question 17

Economists use the Lorenz curve to model income distribution. Let $x$ be the percentage of households, ordered poorest to richest, and $y$ the total income percentage. The line $y=x$ represents equal incomes; the area between it and $y=f(x)$ for $0\le x\le100$ represents income inequality. The source says the US model in 2005 is $y=(0.00061x^2+0.0218x+1723)^2$, $0\le x\le100$. Find the inequality, rounding to the nearest million. The literal printed constant is 1723, without a decimal point. Editorial answer-entry clarification: enter the full rounded integer area, not its numerical coefficient in millions.

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