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\(a,\frac{3}{15}+\frac{2}{5}=\frac{1}{5}+\frac{2}{5}=\frac{3}{5}.\)
\(b,\frac{9}{8}-\frac{5}{6}=\frac{7}{24}\)
\(c,\frac{1}{2}+\frac{3}{7}+\frac{11}{14}=\frac{13}{14}+\frac{11}{14}=\frac{24}{14}=\frac{12}{7}\)
\(d,\frac{8}{3}-\frac{1}{2}-1=\frac{13}{6}-1=\frac{7}{6}\)
~~~ học tốt ~~~
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\(\frac{16}{3}:\frac{8}{3}=\frac{16}{3}\times\frac{3}{8}=\frac{16}{8}=2\)
\(\frac{63}{35}:\frac{21}{5}=\frac{63}{35}.\frac{5}{21}=\frac{3}{7}.\frac{1}{1}=\frac{3}{7}\)
\(\frac{8}{14}\times\frac{7}{8}=\frac{7}{14}=\frac{1}{2}\)
\(\frac{19}{14}\times\frac{7}{15}=\frac{19}{2}\times\frac{1}{15}=\frac{19}{30}\)
\(a,\frac{16}{3}:\frac{8}{3}=\frac{16}{3}\times\frac{3}{8}=\frac{8\times2\times3}{3\times8}=2\)
\(b,\frac{63}{35}:\frac{21}{5}=\frac{63}{35}\times\frac{5}{21}=\frac{21\times3\times5}{5\times7\times21}=\frac{3}{7}\)
\(c,\frac{8}{14}\times\frac{7}{8}=\frac{8\times7}{7\times2\times8}=\frac{1}{2}\)
\(d,\frac{19}{14}\times\frac{7}{15}=\frac{19\times7}{7\times2\times15}=\frac{19}{30}\)
Học tốt
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\(\frac{3}{7}+\frac{4}{9}+\frac{8}{14}+\frac{10}{18}=\frac{3}{7}+\frac{8}{14}+\frac{4}{9}+\frac{10}{18}\)
\(=\frac{14}{14}+\frac{18}{18}=1+1=2\)
chúc bạn học giỏi
\(\frac{3}{7}+\frac{4}{9}+\frac{8}{14}+\frac{10}{18}=\left(\frac{6}{14}+\frac{8}{14}\right)+\left(\frac{8}{18}+\frac{10}{18}\right)=1+1=2\\\)2
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12/14 + 15/20 + 6/7 + 3/4
= ( 12/14 + 6/7 ) + ( 15/20 + 3/4 )
= ( 6/7 + 6/7 ) + ( 3/4 + 3/4 )
= 12/7 + 6/4
= 48/28 + 42/28
= 90/28
= 45/14
Tham khảo nha !!!
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= (9/5 + 6/5) + 4/9 + 8/7 + 3/2 = 3 + (100/63 + 3/2) = 389/126 + 3 = 767/126
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\(a.\dfrac{3\times4\times7}{12\times8\times9}=\dfrac{3\times4\times7}{3\times4\times4\times2\times9}\\ =\dfrac{7}{4\times2\times9}=\dfrac{7}{72}\\ b.\dfrac{4\times5\times6}{12\times10\times8}=\dfrac{4\times5\times2\times3}{4\times3\times5\times2\times4\times2}=\dfrac{1}{8}\\ c.\dfrac{5\times6\times7}{12\times14\times15}=\dfrac{5\times6\times7}{2\times6\times7\times2\times5\times3}\\ =\dfrac{1}{2\times2\times3}=\dfrac{1}{12}\)
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a)\(\frac{2}{3}:\frac{4}{9}+\frac{1}{3}:\frac{4}{9}\)
=\(\frac{4}{9}:\left(\frac{2}{3}+\frac{1}{3}\right)\)
=\(\frac{4}{9}:1=\frac{4}{9}\)
b
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a ) \(\frac{5}{7}\) + \(\frac{7}{14}\)
= \(\frac{10}{14}\) + \(\frac{7}{14}\)
= \(\frac{10+7}{14}\)= \(\frac{17}{14}\)
b ) \(\frac{5}{3}\) + \(\frac{9}{12}\) + \(\frac{8}{9}\)
= \(\frac{20}{12}\) + \(\frac{9}{12}\) + \(\frac{8}{9}\)
= \(\frac{29}{12}\) + \(\frac{8}{9}\)
= \(\frac{357}{108}\)