Question

3/7+2/21-3/14

5/4-5/12+3/8

7/12x8/21:2/3

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Answer 1

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Answer 2

\(\frac{3}{7}+\frac{2}{21}-\frac{3}{14}\)

\(=\frac{11}{21}-\frac{3}{14}=\frac{13}{42}\)

\(\frac{5}{4}-\frac{5}{12}+\frac{3}{8}\)

\(=\frac{5}{6}+\frac{3}{8}=\frac{29}{24}\)

\(\frac{7}{12}.\frac{8}{21}:\frac{2}{3}\)

\(=\frac{2}{9}:\frac{2}{3}=\frac{1}{3}\)

 

Answer 3

\(\frac{3}{7}+\frac{2}{21}-\frac{3}{14}\)

= \(\frac{9}{21}+\frac{2}{21}-\frac{3}{14}\)

=\(\frac{11}{21}-\frac{3}{14}\)

=...

\(\frac{5}{4}-\frac{5}{12}+\frac{3}{8}\)

=\(\frac{15}{12}-\frac{5}{12}+\frac{3}{8}\)

=\(\frac{5}{6}+\frac{3}{8}\)

=\(\frac{40}{48}+\frac{18}{48}\)

=\(\frac{58}{48}=\frac{29}{24}\)

\(\frac{7}{12}\cdot\frac{8}{21}:\frac{2}{3}\)

=\(\frac{2}{9}:\frac{2}{3}=\frac{2}{9}.\frac{3}{2}\)

=\(\frac{1}{3}\)