Question

3 efetue isso e fração exemplo dois sombre tres ; e se pricisa faze o mm c fale quanto deu ta porquê vale metade da milha nota a) 2/3+1/2+5/4 b) 3/7 _ 1/14 + 5/21 c) 3/4 . 4/5 d)1/2 . 1/3 . 3/4 . 2/5 e) 3/6 ;1/2

Answer 1

a) mmc(3,2,4) = 3 2 4 |2
                     3 1 2|2
                     3 1 1|3
                      1 1 1
mmc(3,2,4) = 2x2x3 = 12

$\frac{2}{3} + \frac{1}{2} + \frac{5}{4} = \frac{4.2 + 6.1 + 3.5}{12} = \frac{29}{12}$

b) $\frac{3}{7} - \frac{1}{14} + \frac{5}{21}$

mmc(7,14,21) =

7  14  21|2
7    7  21|3
7    7    7|7
1    1    1

mmc(7,14,21) = 2x3x7 = 42

$\frac{3}{7} - \frac{1}{14} + \frac{5}{21} = \frac{6.3 - 3.1 + 2.5}{42} = \frac{25}{42}$

c)$\frac{3}{4} . \frac{4}{5} = \frac{3.4}{4.5} = \frac{12}{20} = (simplificando) = \frac{3}{5}$

d) $\frac{1}{2} . \frac{1}{3} . \frac{3}{4} . \frac{2}{5} = \frac{1 . 1 . 3 . 2}{2 . 3 .4 . 5} = \frac{6}{120} = \frac{1}{20}$

e) $\frac{3}{6} : \frac{1}{2} = \frac{ \frac{3}{6} }{ \frac{1}{2} } = \frac{3}{6} . \frac{2}{1} = \frac{6}{6} = 1$