a.
\(-\frac{7}{31}+\left(\frac{24}{17}+\frac{7}{31}\right)=-\frac{7}{31}+\frac{7}{31}+\frac{24}{17}=\frac{24}{17}\)
b.
\(\frac{3}{7}+\left(-\frac{1}{5}+\frac{-3}{7}\right)=\frac{3}{7}-\frac{3}{7}-\frac{1}{5}=-\frac{1}{5}\)
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b) \(-\frac{7}{31}+\left(\frac{24}{14}+\frac{7}{31}\right)\)
\(=-\frac{7}{31}+\frac{24}{17}+\frac{7}{31}\)
\(=\left(-\frac{7}{31}+\frac{7}{31}\right)+\frac{24}{17}\)
\(=0+\frac{24}{17}=\frac{24}{17}\)
c) \(\frac{3}{7}+\left(-\frac{1}{5}+\left(-\frac{3}{7}\right)\right)\)
\(=\frac{3}{7}-\frac{1}{5}-\frac{3}{7}\)
\(=\left(\frac{3}{7}-\frac{3}{7}\right)-\frac{1}{5}\)
\(=0-\frac{1}{5}=-\frac{1}{5}\)
b) -7/31+(24/17+3/31) = -7/31+24/17+7/31= (-7/31+7/31)+24/17= 0+24/17=24/17
c) 3/7+(-1/5+-3/7)= 3/7+-1/5+-3/7= ( 3/7+-3/7)+-1/5= 0+-1/5 = -1/5
b) -7/31+(24/17+7/31)
= -7/31+863/527
= 24/17
c) 3/7+(-1/5+-3/7)
= 3/7+-22/35
= -1/5
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