Question

a/b+c/d,para a = 20,b = 5 ,c =81 e d=9​

Answer 1

$\frac{a}{b} + \frac{c}{d} \\ \\ \frac{20}{5} + \frac{81}{9} = \frac{180 + 405}{45} = \frac{585}{45} = 13$

ou simplesmente

$\frac{20}{5} + \frac{81}{9} = 4 + 9 = 13$