Question

21/13 : 7/39 - 2/5 = ? giúp mình với

 

Answer 1

\(\dfrac{21}{13}:\dfrac{7}{39}-\dfrac{2}{5}=\dfrac{21}{13}\times\dfrac{39}{7}-\dfrac{2}{5}=21\times\dfrac{3}{7}-\dfrac{2}{5}=9-\dfrac{2}{5}=\dfrac{45}{5}-\dfrac{2}{5}=\dfrac{43}{5}\)

Answer 2

\(\dfrac{21}{13}\) : \(\dfrac{7}{39}\) - \(\dfrac{2}{5}\) = 9 - \(\dfrac{2}{5}\) = \(\dfrac{43}{5}\)