c1 :(5/4 + 2/5) : 5/6 = 33/20 : 5/6 = 99/50
c2 :(5/4 + 2/5) : 5/6 = 5/4 : 5/6 + 2/5 : 5/6 =99/50
c1 : 3/4 x 2/5 - 3/4 x 2/7 = 3/4 x (2/5 - 2/7) = 3/4 x 4/35 = 3/35
c2 : 3/4 x 2/5 - 3/4 x 2/7 = 3/35
c1 : 2/3 : (5/6 x 9/10) = 2/3 : 3/4 = 8/9
c2 : 2/3 : (5/6 x 9/10) = 5/6 : 2/3 x 9/10 : 2/3 = 27/16 * cái này chx chắc:"> quên mất cách lm;-;"" "
a ) ( \(\dfrac{5}{4}+\dfrac{2}{5}\)) : \(\dfrac{5}{6}\) = ?
C1 :(\(\dfrac{5}{4}\) + \(\dfrac{2}{5}\)) : \(\dfrac{5}{6}\) = \(\dfrac{33}{20}\) : \(\dfrac{5}{6}\) = \(\dfrac{99}{50}\)
C2 :(\(\dfrac{5}{4}\) + \(\dfrac{2}{5}\)) : \(\dfrac{5}{6}\) = \(\dfrac{5}{4}\) : \(\dfrac{5}{6}\) + \(\dfrac{2}{5}\) : \(\dfrac{5}{6}\) =\(\dfrac{99}{50}\)
b )\(\dfrac{3}{4}\) x \(\dfrac{2}{5}\) - \(\dfrac{3}{4}\) x\(\dfrac{2}{7}\) = ?
C1 : \(\dfrac{3}{4}\) x \(\dfrac{2}{5}\) - \(\dfrac{3}{4}\) x \(\dfrac{2}{7}\) = \(\dfrac{3}{4}\) x (\(\dfrac{2}{5}\) - \(\dfrac{2}{7}\)) = \(\dfrac{3}{4}\) x \(\dfrac{4}{35}\) = \(\dfrac{3}{35}\)
C2 : \(\dfrac{3}{4}\) x \(\dfrac{2}{5}\) - \(\dfrac{3}{4}\) x \(\dfrac{2}{7}\) = \(\dfrac{3}{35}\)
c ) \(\dfrac{2}{3}\) : ( \(\dfrac{5}{6}x\dfrac{9}{10}\)) = ?
C1 : \(\dfrac{2}{3}\) : (\(\dfrac{5}{6}x\dfrac{9}{10}\)) = \(\dfrac{2}{3}\): \(\dfrac{3}{4}\) = \(\dfrac{8}{9}\)C2 : \(\dfrac{2}{3}\) : (\(\dfrac{5}{6}\) x\(\dfrac{9}{10}\)) = \(\dfrac{5}{6}\) : \(\dfrac{2}{3}\) x\(\dfrac{9}{10}\) : \(\dfrac{2}{3}=\dfrac{27}{16}\)