Tính hợp lý
\(\frac{-5}{7}\). \(\frac{6}{19}\)+ \(\frac{13}{-7}\). \(\frac{5}{19}\)- \(\frac{15}{7}\)
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Những câu hỏi liên quan
1 tháng 4 2016
\(\frac{-3}{5}.\left(\frac{5}{7}+\frac{3}{7}+\frac{6}{7}\right)\)
=\(\frac{-3}{5}.\)\(\frac{14}{7}\)
=\(-\frac{3}{5}.2\)
=-6/5
12 tháng 8 2016
A = -10/3 + 19/6.7/5 - 19/3.1/10 + 19/10.4/3
A = 1/30.(-10.10 + 19.7 - 19.1 + 19.4)
A = 1/30.(-100 + 19.11 - 19)
A = 1/30.(-100 + 19.10)
A = 1/30.(-100 + 190)
A = 1/30.90
A = 3
NH
27 tháng 3 2019
\(a.\frac{108}{119}.\frac{107}{211}+\frac{108}{119}.\frac{104}{211}=\frac{108}{119}.\left(\frac{107}{211}+\frac{104}{211}\right)=\frac{108}{119}.1=108\)
VL
1
KN
19 tháng 4 2019
\(\frac{-5}{7}.\frac{6}{19}+\frac{13}{-7}.\frac{5}{19}-\frac{15}{7}\)
\(=\frac{-30}{133}+\frac{65}{-133}-\frac{15}{7}\)
\(=\frac{-30}{133}+\frac{-65}{133}-\frac{15}{7}\)
\(=\frac{-95}{133}-\frac{285}{133}\)
\(=\frac{-380}{133}\)
VL
3
B
15 tháng 4 2019
\(\frac{-5}{7}.\frac{6}{19}+\frac{13}{-7}-\frac{5}{19}-\frac{15}{7}\)
\(=-\frac{5}{7}.\frac{6}{19}+\frac{-13}{7}-\frac{5}{19}-\frac{15}{7}\)
\(=\left(\frac{-5}{7}+\frac{-13}{7}-\frac{15}{7}\right).\left(\frac{6}{19}-\frac{5}{19}\right)\)
\(=\frac{-23}{7}.\frac{1}{19}\)
\(=\frac{-23}{133}\)
15 tháng 4 2019
\(\frac{-5}{7}.\frac{6}{19}+\frac{13}{-7}-\frac{5}{19}-\frac{15}{7}\)
\(=\frac{-5}{6}.\frac{6}{19}+\frac{-13}{7}+\frac{-5}{19}+\frac{-15}{7}\)
\(=\frac{-5}{19}+\frac{-13}{7}+\frac{-5}{19}+\frac{-15}{7}\)
\(=\left(\frac{-5}{19}+\frac{-5}{19}\right)+\left(\frac{-13}{7}+\frac{-15}{7}\right)\)
\(=\frac{-10}{19}+\frac{-26}{7}\)
\(=\frac{-564}{133}\)
NN
31 tháng 8 2020
b) \(\frac{12}{19}.\frac{7}{15}.\frac{-13}{17}.\frac{19}{12}.\frac{17}{13}=\frac{12}{19}.\frac{19}{12}.\frac{-13}{17}.\frac{17}{13}.\frac{7}{15}=1.\left(-1\right).\frac{7}{15}=\frac{-7}{15}\)
31 tháng 8 2020
\(-\frac{5}{7}.\frac{2}{11}+-\frac{5}{7}.\frac{9}{14}+\frac{12}{7}=-\frac{5}{7}.\left(\frac{2}{11}+\frac{9}{14}\right)+\frac{12}{7}=-\frac{5}{7}.\frac{127}{154}+\frac{12}{7}=-\frac{635}{1078}+\frac{12}{7}=\frac{1213}{1078}\)
\(\frac{12}{19}.\frac{7}{15}.-\frac{13}{17}.\frac{19}{12}.\frac{17}{13}=\left(\frac{12}{19}.\frac{19}{12}\right).\left(-\frac{13}{17}.\frac{17}{13}\right).\frac{7}{15}=1.-1.\frac{7}{15}=-\frac{7}{15}\)
1 tháng 7 2018
\(\frac{7}{13}.\frac{5}{19}+\frac{7}{19}.\frac{8}{13}-3\frac{7}{19}\)
\(=\frac{7}{19}.\frac{5}{13}+\frac{7}{19}.\frac{8}{13}-3-\frac{7}{19}\)
\(=\frac{7}{19}\left(\frac{5}{13}+\frac{8}{13}\right)-3-\frac{7}{19}\)
\(=\frac{7}{19}-3-\frac{7}{19}\)
\(=-3\)
1 tháng 7 2018
\(\frac{7}{13}.\frac{5}{19}+\frac{7}{19}.\frac{8}{13}-3\frac{7}{19}\)
=\(\frac{7}{19}.\frac{5}{13}+\frac{7}{19}.\frac{8}{13}-3-\frac{7}{19}\)
= \(\frac{7}{19}.\left(\frac{5}{13}+\frac{8}{13}\right)-3-\frac{7}{19}\)
= \(\frac{7}{19}-3-\frac{7}{19}\) = \(-3\)
\(\frac{-5}{7}.\frac{6}{19}+\frac{13}{-7}.\frac{5}{19}-\frac{15}{7}=\frac{-5}{7}.\frac{6}{19}+\frac{13}{19}.\frac{-5}{7}+\frac{-5}{7}.3\)
\(=\frac{-5}{7}.\left(\frac{6}{19}+\frac{13}{19}+3\right)=\frac{-5}{7}.4=\frac{-20}{7}\)