Question

Alguém pode me ajudar nessa e/ou me explicar como fazer? Preciso muito mesmo disso e se alguém me ajudar ficarei muito agradecida!

Answer 1

A)

$( \frac{3}{4} \times \frac{1}{2} + \frac{2}{5} ) + \frac{1}{4} =\\\\ (\frac{3}{8} + \frac{2}{5} )+ \frac{1}{4} =\\ \\ ( \frac{15 + 16}{40} ) + \frac{1}{4} =\\\\ \frac{31}{40} + \frac{1}{4} =\\\\ \frac{31 + 10}{40} =\\\\ \frac{41}{40}$

B)

$( \frac{2}{3} \times \frac{1}{4} ) + ( \frac{1}{3} \times \frac{1}{2} ) =\\\\ \frac{2}{12} + \frac{1}{6} =\\\\ \frac{2 + 2}{12} =\\\\ \frac{4}{12} =\\\\ \frac{1}{3}$

C)

$(5 - \frac{1}{2} ) - (2 - \frac{1}{3} ) =\\\\ ( \frac{5}{1} - \frac{1}{2} ) - ( \frac{2}{1} - \frac{1}{3} ) =\\\\ (\frac{10 - 1}{2} ) - (\frac{6 -1 }{3} ) =\\\\ \frac{9}{2} - \frac{5}{3} =\\\\ \frac{27 - 10}{6} =\\\\ \frac{17}{6}$

D)

$(3\times \frac{5}{2} ) - (\frac{1}{5} +\frac{1}{3} ) =\\\\\\(\frac{3}{1} \times \frac{5}{2} ) - (\frac{1}{5} +\frac{1}{3} )=\\\\\frac{15}{2} -\frac{3+5}{15} =\\\\\frac{15}{2}-\frac{8}{15}=\\\\\frac{225-16}{30}=\\\\\frac{209}{30}$

e)

$(3\times\frac{3}{4} )+(3\times\frac{1}{4} ) =\\\\(\frac{3}{1} \times \frac{3}{4} )+ (\frac{3}{1} \times \frac{1}{4} )=\\\\\frac{9}{4} +\frac{3}{4}= \\\\\frac{9+3}{4} =\\\\\frac{12}{4} =\\\\3$

F)

$(3+\frac{1}{2} )\times\frac{4}{5} -\frac{3}{10} =\\\\(\frac{3}{1} +\frac{1}{2} )\times \frac{4}{5} -\frac{3}{10} =\\\\(\frac{6+1}{2} )\times \frac{4}{5} -\frac{3}{10} =\\\\\frac{7}{2} \times \frac{4}{5} - \frac{3}{10} =\\\\\frac{28}{10} - \frac{3}{10} =\\\\\\\frac{28-3}{10} =\\\\\\\frac{25}{10} =\\\\\\\frac{5}{2}$

Métodos a usar nessas questões:

Multiplicaçao

Mmc = mínimo múltiplo comum

obs: Veja a resposta pelo pc, pq pelo celular as contas ficam bugadas.