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mori ran

tinh

a 7/15 + (5/6 - 1/3) =

b 4/7 *21/16 : 5/8 =

c 15/8 - 4/9 * 6/8+ 1/6 =

d 5/12+(3/4 + 2/3 ) : 34/3 =

 

l҉o҉n҉g҉ d҉z҉
24 tháng 5 2016 lúc 12:09

a 7/15 + (5/6 - 1/3) = 7/15 + 1/2 = 14/30 + 15/30 = 29/30

b 4/7 *21/16 : 5/8 = 3/4  : 5/8 = 6/5

c 15/8 - 4/9 * 6/8+ 1/6 =15/8 - 1/3 + 1/6 = 37/24 + 1/6 = 41/24

d 5/12+(3/4 + 2/3 ) : 34/3 =

Huỳnh Châu Giang
24 tháng 5 2016 lúc 12:10

a/\(\frac{7}{15}+\left(\frac{5}{6}-\frac{1}{3}\right)=\frac{7}{15}+\frac{1}{2}=\frac{29}{30}\)

b/\(\frac{4}{7}\cdot\frac{21}{16}:\frac{5}{8}=\frac{4}{7}\cdot\frac{2}{16}\cdot\frac{8}{5}=\frac{4}{35}\)

c/\(\frac{15}{8}-\frac{4}{9}\cdot\frac{6}{8}+\frac{1}{6}=\frac{15}{8}-\frac{1}{3}+\frac{1}{6}=\frac{41}{24}\)

d/ \(\frac{5}{12}+\left(\frac{3}{4}+\frac{2}{3}\right):\frac{34}{3}=\frac{5}{12}+\frac{17}{12}:\frac{34}{3}=\frac{5}{12}+\frac{1}{8}=\frac{13}{24}\)

NaRuGo
24 tháng 5 2016 lúc 12:19

a/   \(\frac{7}{15}+\left(\frac{5}{6}-\frac{1}{3}\right)\)

\(\frac{7}{15}+\frac{1}{2}\)

\(\frac{29}{30}\)

b/ \(\frac{4}{7}.\frac{21}{16}:\frac{5}{8}\)

\(\frac{4}{7}.\frac{21}{16}.\frac{8}{5}\)

\(\frac{6}{5}\)

c/ \(\frac{15}{8}-\frac{4}{9}.\frac{6}{8}+\frac{1}{6}\)

\(\frac{15}{8}-\frac{1}{3}+\frac{1}{6}\)

\(\frac{41}{24}\)

d/ \(\frac{5}{12}+\left(\frac{3}{4}+\frac{2}{3}\right):\frac{34}{3}\)

\(\frac{5}{12}+\frac{17}{12}\)\(:\frac{34}{3}\)

\(\frac{5}{12}+\frac{1}{8}\)

\(\frac{13}{24}\)