Explicación paso a paso:
[tex] \frac{3}{5} - \frac{8}{7} = [/tex]
21+40 = 61
35 31
+
[tex] \frac{3}{4} - \frac{9}{2} = [/tex]
6-36 = 30 = 15
8 8 4
[tex] \frac{2}{1} + \frac{1}{2 = } [/tex]
