\(\dfrac{4}{3}+\dfrac{5}{21}=\dfrac{28}{21}+\dfrac{5}{21}=\dfrac{33}{21}\)
\(\dfrac{4\times7}{3\times7}+\dfrac{5}{21}=\dfrac{28}{21}+\dfrac{5}{21}=\dfrac{33}{21}\)
a)\(\dfrac{3}{5}\)+\(\dfrac{17}{21}\)*\(\dfrac{17}{21}\)+\(\dfrac{3}{5}\)
b)\(\dfrac{15}{8}\):\(\dfrac{5}{20}\)-\(\dfrac{7}{8}\):\(\dfrac{1}{4}\)
6. ÉT O ÉT
\(\dfrac{9}{7}\) và \(\dfrac{5}{6}\) \(\dfrac{4}{7}\) và \(\dfrac{8}{21}\) \(\dfrac{2}{5};\dfrac{1}{3}\) và \(\dfrac{1}{2}\) \(\dfrac{1}{3};\dfrac{4}{3}\) và\(\dfrac{1}{5}\)
\(xx\dfrac{2}{7}x\dfrac{3}{4}=\dfrac{5}{21}\)
\(a.\dfrac{3}{5}\) x \(\dfrac{17}{21}\) \(+ \) \(\dfrac{17}{21}\) x \(\dfrac{2}{5}\)
\(b.(\dfrac{8}{5}+\dfrac{5}{6}):\dfrac{7}{6}\)
98775 - 32 x 85 / 67500 - 24 x 236 / 568 + 101598 : 287 / 6875 + 980 -180 \(\dfrac{2}{5}+\dfrac{3}{10}-\dfrac{1}{2}\) / \(\dfrac{8}{11}+\dfrac{8}{33}\) x \(\dfrac{3}{4}\) / 7/9 x 3/14 :5/8 / \(\dfrac{5}{12}-\dfrac{7}{32}:\dfrac{21}{16}\)
ÉT O ÉT
\(\dfrac{4}{7}\)x\(\dfrac{21}{16}\):\(\dfrac{5}{8}\)
\(\dfrac{4}{7}\)x\(\dfrac{21}{16}\):\(\dfrac{5}{8}\)
Mẫu số chung nhỏ nhất của ba phân số \(\dfrac{2}{3}\) ; \(\dfrac{4}{5}\) ; \(\dfrac{6}{7}\)là:
A. 15 B. 35 C. 21 D. 105
Tính nhanh:\((\) \(\dfrac{1}{3}\)-\(\dfrac{1}{5}\)-\(\dfrac{1}{10}\)-\(\dfrac{1}{30}\))x(\(\dfrac{1}{21}\)+\(\dfrac{1}{210}\)+\(\dfrac{1}{2010}\))
