a) \(\dfrac{2\cdot7\cdot13}{26\cdot35}=\dfrac{2\cdot7\cdot13}{2\cdot13\cdot5\cdot7}=\dfrac{1}{5}\)
b) \(\dfrac{31\cdot7-13}{4-35}=\dfrac{217-13}{-31}=\dfrac{-204}{31}\)
c) \(\dfrac{32\cdot7-32\cdot4}{38-35}=\dfrac{32\cdot\left(7-4\right)}{3}=\dfrac{32\cdot3}{3}=32\)
d) \(\dfrac{1717-101}{2828+202}=\dfrac{1616}{3030}=\dfrac{8}{15}\)
e) \(\dfrac{3\cdot6+2\cdot9\cdot5-18\cdot\left(-4\right)}{7\cdot\left(-7\right)+12\cdot\left(-7\right)+7}\)
\(=\dfrac{18+18\cdot5+18\cdot4}{7\cdot\left(-7\right)-12\cdot7+7}\)
\(=\dfrac{18\cdot\left(1+5+4\right)}{7\cdot\left(-7-12+1\right)}\)
\(=\dfrac{18\cdot10}{7\cdot\left(-18\right)}\)
\(=\dfrac{-10}{7}\)
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