Question

calcule as expressões
a) 3/5 - 1- 2/5
b)4-1/10 + 2/5
c)1/2-(3/5+7/10)
d)-2-(1/2)-1/8
e)5/12+(-1/4)-(1/6)​

Answer 1

a)

$\frac{3}{5} - 1 - \frac{2}{5} = \\ \frac{3}{5} - \frac{5}{5} - \frac{2}{5} = \\ \frac{3}{5} - \frac{7}{5} = - \frac{4}{5} \: ou \: - 0.8$

b)

$4 - \frac{1}{10} + \frac{2}{5} = \\ \frac{4}{1} - \frac{1}{10} + \frac{2}{5} = \\ \frac{40}{10} - \frac{1}{10} + \frac{4}{10} = \frac{43}{10} \: ou \: 4.3$

c)

$\frac{1}{2} - ( \frac{3}{5} + \frac{7}{10} ) = \\ \frac{1}{2} - ( \frac{6 + 7}{10} ) = \\ \frac{1}{2} - \frac{13}{10} = \\ \frac{5}{10} - \frac{13}{10} = - \frac{8}{10} \: ou \: - 0.8$

d)

$- \frac{2}{1} - \frac{1}{2} - \frac{1}{8} = \\ - \frac{16}{8} - \frac{4}{8} - \frac{1}{8} = \\ - \frac{21}{8} \: ou \: - 2.625$

e)

$\frac{5}{12} + ( - \frac{1}{4} ) - ( \frac{1}{6} ) = \\ \frac{5}{12} - \frac{1}{4} - \frac{1}{6} = \\ \frac{5}{12} - \frac{3}{12} - \frac{2}{12} = \\ \frac{5}{12} - \frac{5}{12} = 0$

Estarei à disposição para qualquer dúvida, bons estudos! :)