a) Cách 1:
\(\dfrac{7}{11}\) \(:\dfrac{3}{5}\) \(+ \dfrac{4}{11}\) \(: \dfrac{3}{5}\)
\(= \dfrac{7}{11} \times \dfrac{5}{3}+ \dfrac{4}{11} \times \dfrac{5}{3}\)
\(= \dfrac{35}{33}+ \dfrac{20}{33}\)
\(=\dfrac{55}{33}= \dfrac{5}{3}\)
Cách 2:
\(\dfrac{7}{11}: \dfrac{3}{5}+ \dfrac{4}{11} :\dfrac{3}{5}\)
\(= \left( \dfrac{7}{11} + \dfrac{4}{11} \right ) : \dfrac{3}{5}\)
\(= \dfrac{11}{11} : \dfrac{3}{5}\)
\(= 1: \dfrac{3}{5} = \dfrac{5}{3}\)
b) Cách 1 :
\( (6,24 + 1,26) : 0,75\)
\(= 7,5 : 0,75 = 10 \)
Cách 2:
\( (6,24 + 1,26) : 0,75 \)
\(= 6,24 : 0,75 + 1,26 : 0,75 \)
\(= 8,32 + 1,68 = 10 \).
