\textbf{141.} The unemployment rate of a country over 10 years is given below. What is the value of $\dfrac{Q_1 + Q_3 - 2Q_2}{Q_3 - Q_1}$?
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\fbox{$11.5,\ 12.8,\ 13.5,\ 11.2,\ 12.3,\ 12.6,\ 11.9,\ 10.6,\ 10.2,\ 30,\ 12.7$}
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(1) $-0.225$ \hfill (2) $-0.125$ \hfill (3) $0.175$ \hfill (4) $0.275$
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