Question

calcule e assinale o resultado correto:
0,27777....+ 2,3333...
a) 18/47
b)43/18
c)47/18
d)18/43

Answer 1

$0,27777...= \frac{27-2}{90}= \frac{25}{90} \\ \\2,3333...= 2+0,333...=2+\frac{3}{9}= \frac{18}{9}+\frac{3}{9}=\frac{18+3}{9} =\frac{21}{9} \\ \\0,27777....+ 2,3333...= \frac{25}{90} +\frac{21}{9}= \frac{25}{90} + \frac{210}{90} = \frac{25+210}{90} = \frac{235^{:5}}{90_{:5}} = \frac{47}{18}$$0,27777...= \frac{27-2}{90}= \frac{25}{90} \\ \\2,3333...= 2+0,333...=2+\frac{3}{9}= \frac{18}{9}+\frac{3}{9}=\frac{18+3}{9} =\frac{21}{9} \\ \\0,27777....+ 2,3333...= \frac{25}{90} +\frac{21}{9}= \frac{25}{90} + \frac{210}{90} = \frac{25+210}{90} = \frac{235^{:5}}{90_{:5}} = \frac{47}{18}$

Answer 2

Fração geratriz de 0,2777... = $\frac{25}{90}$
FRação geratriz de 2,3333.... = 2 + $\frac{3}{9}$

Então: $\frac{25}{90} + 2 + \frac{3}{9} = \frac{25 + 180 + 30}{90} = \frac{235}{90} = \frac{47}{18}$

resposta c