Respuesta :

Hello , 

40/21 = 21/21 + 19/21
40/21 =     1     + 19/21
40/21 = 1  [tex] \frac{19}{21} [/tex]
[tex]\dfrac{40}{21}=\dfrac{21+19}{21}=\dfrac{21}{21}+\dfrac{19}{21}=1+\dfrac{19}{21}=\boxed{1\dfrac{19}{21}}[/tex]