D= (\(\frac{30}{5}\)- \(\frac{11}{5}\)):\(\frac{25}{8}\)-\(\frac{8}{5}\):\(\frac{1}{4}\)
D=\(\frac{19}{5}\).\(\frac{8}{25}\)- \(\frac{8}{5}\).\(\frac{4}{1}\)
D=\(\frac{152}{125}\)-\(\frac{32}{5}\)
D=\(\frac{152}{125}\)-\(\frac{800}{125}\)
D=\(\frac{-648}{125}\)=
Giải
D= \(\left(6-2\frac{1}{5}\right):3\frac{1}{8}-1\frac{3}{5}:\frac{1}{4}\)
= \(4\frac{1}{5}:3\frac{1}{8}-1\frac{3}{5}:\frac{1}{4}\)
= \(\frac{21}{5}:\frac{25}{8}-\frac{8}{5}:\frac{1}{4}\)
= \(\left(\frac{21}{5}:\frac{8}{5}\right)-\left(\frac{25}{8}:\frac{1}{4}\right)\)
= \(\left(\frac{21}{5}.\frac{5}{8}\right)-\left(\frac{25}{8}.\frac{4}{1}\right)\)
= \(\frac{21}{8}-\frac{25}{2}\)
= \(\frac{21}{8}-\frac{100}{8}\)
= \(\frac{-79}{8}\)
D = (6 - 2/1/5) : 3/1/8 - 1/3/5 : 1/4
= 4/1/5 : 3/1/8 - 1/3/5 : 1/4
= 21/5 : 25/8 - 8/5 : 1/4
= ( 21/5 : 8/5 ) - ( 25/8 : 1/4 )
= (21/5 . 5/8 ) - (25/8 . 4/1 )
= 21/8 - 25/2
= 21/8 - 100/8 = -79/8
