Question

Calcule o resultado das operações
a)2/9+5/9
b)5/6-2/6
c)3/4+1/5
d)7/8-4/9
é)1/7+3/5+9/14
f)3-14/5

Answer 1

Resposta:

a) 7/9             d) 31/72

b) 1/2              e)97/70

c) 19/20          f) 1/5

Explicação passo-a-passo:

a) $\frac{2}{9} + \frac{5}{9} = \frac{7}{9}$

b) $\frac{5}{6} - \frac{2}{6} = \frac{3}{6} = \frac{1}{2}$

c) $\frac{3}{4} + \frac{1}{5}  =$

   MMC = 20

   $\frac{(20:4).3}{20} + \frac{(20:5).1}{20} = \frac{15 + 4}{20} = \frac{19}{20}$

d) $\frac{7}{8} - \frac{4}{9} =$

    $\frac{(72:8).7}{72} - \frac{(72:9).4}{72} =$

   $\frac{63}{72} - \frac{32}{72} =$

   $\frac{31}{72}$

e) $\frac{1}{7} + \frac{3}{5} + \frac{9}{14} =$

  $\frac{(70:7).1}{70} + \frac{(70:5).3}{70} + \frac{(70:14).9}{70} =$

$\frac{10 + 42 + 45}{70} =$

  $\frac{97}{70}$

f) 3 - $\frac{14}{5} =$

 $\frac{15 - 14}{5} =$

$\frac{1}{5}$