Khó với cả nhiều nhưng các bạn cố gắng làm nhé !!!! Các giáo viên vào giúp em với
Bài 1 Tính giá trị biểu thức :
a) \(\left(2\frac{5}{6}+1\frac{4}{9}\right):\left(10\frac{1}{12}+9\frac{1}{2}\right)\)
b) \(\left(9\frac{1}{2}-8,75\right):\frac{2}{7}+0,625:1\frac{2}{3}\)
c) 140 x \(\left(\frac{505050}{565656}+\frac{505050}{727272}+\frac{505050}{909090}\right)\)
d) \(\frac{\frac{7}{5}-\frac{7}{25}+\frac{7}{125}-\frac{7}{625}}{1-\frac{1}{5}+\frac{1}{25}-\frac{1}{125}}\)
a, \(\left(\frac{17}{6}+\frac{13}{9}\right):\left(\frac{121}{12}+\frac{19}{2}\right)\)
\(=\frac{77}{18}:\frac{235}{12}=\frac{77}{18}.\frac{12}{235}=\frac{154}{705}\)
b, \(\left(\frac{19}{2}-\frac{35}{4}\right).\frac{7}{2}+\frac{5}{8}:\frac{5}{3}\)
\(\frac{3}{4}.\frac{7}{2}+\frac{5}{8}.\frac{3}{5}=\frac{21}{8}+\frac{3}{8}=\frac{24}{8}=3\)
c, \(140.\left(\frac{25}{28}+\frac{25}{36}+\frac{5}{9}\right)=140.\frac{10}{7}=200\)
d, \(\left(\frac{7}{5}-\frac{7}{25}+\frac{7}{125}-\frac{7}{625}\right):\left(1-\frac{1}{5}+\frac{1}{25}-\frac{1}{125}\right)\)
\(=\frac{728}{625}:\frac{104}{125}=\frac{728}{625}.\frac{125}{104}=\frac{7}{5}\)
c)=140[(50.10101)/(56.10101)+(50.10101)/(72.10101)+(50.10101)/(90.10101)]
=140(50/56+50/72+50/90)
=140.50(1/56+1/72+1/90)
=7000(1/7.8+1/8.9+1/9.10)
=7000(1/7-1/8+1/8-1/9+1/9-1/10)
=7000(1/7-1/10)
=7000.3/70
=300
