a) 4$\dfrac{5}{7}$ : 1$\dfrac{5}{6}$ + 2$\dfrac{7}{15}$ x $\dfrac{21}{74}$
⇔ $\dfrac{33}{7}$ : $\dfrac{11}{6}$ + $\dfrac{37}{15}$ x $\dfrac{21}{74}$
⇔ $\dfrac{33}{7}$ x $\dfrac{6}{11}$ + $\dfrac{7}{10}$
⇔ $\dfrac{18}{7}$ + $\dfrac{7}{10}$
⇔ $\dfrac{229}{70}$
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b ) 3 $\dfrac{5}{7}$ - 2$\dfrac{5}{7}$ + 6$\dfrac{3}{8}$
= $\dfrac{26}{7}$ - $\dfrac{19}{7}$ + $\dfrac{51}{8}$
= $\dfrac{717}{56}$
c ) 4 $\dfrac{1}{2}$+ $\dfrac{1}{2}$ : 5$\dfrac{1}{2}$
= $\dfrac{9}{2}$ + $\dfrac{1}{2}$ x $\dfrac{2}{11}$
= $\dfrac{9}{2}$+ $\dfrac{1}{11}$
= $\dfrac{101}{22}$
d ) 3$\dfrac{1}{4}$ + $\dfrac{2}{34}$ + $\dfrac{5}{7}$
= $\dfrac{13}{4}$ + $\dfrac{92}{119}$
= $\dfrac{1915}{476}$
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