Các câu hỏi tương tự
tính A = \(\frac{\frac{1}{2}+\frac{1}{6}+\frac{1}{12}+...+\frac{1}{90}}{5+\frac{5}{3}+\frac{5}{6}+\frac{1}{2}+...+\frac{1}{9}}\)
tks
\(\frac{\frac{1}{2}+\frac{1}{6}+\frac{1}{12}+...+\frac{1}{90}}{5+\frac{5}{3}+\frac{5}{6}+\frac{1}{2}+...+\frac{1}{9}}\)
Tính nhanh. M.n giúp dùm nhak. Tks
Tính nhanh:
A=\(\frac{1}{90}-\frac{1}{72}-\frac{1}{56}-\frac{1}{42}-\frac{1}{30}-\frac{1}{20}-\frac{1}{12}-\frac{1}{6}-\frac{1}{2}\)
B=\(\frac{3}{2}-\frac{5}{6}+\frac{7}{12}-\frac{9}{20}+\frac{11}{30}-\frac{13}{42}+\frac{15}{56}-\frac{17}{72}\)
Tính nhanh
a) \(\frac{2}{3}-\left(-\frac{1}{2}\right)+\frac{3}{5}-\frac{7}{45}-\left(-\frac{5}{9}\right)+\frac{1}{12}=\frac{1}{90}\)
b) \(\left(7-\frac{4}{3}+\frac{1}{3}\right)-\left(6+\frac{5}{4}-\frac{4}{3}\right)-\left(5-\frac{7}{4}+\frac{5}{3}\right)\)
Tính nhanh
a) \(\frac{2}{3}-\left(-\frac{1}{2}\right)+\frac{3}{5}-\frac{7}{45}-\left(-\frac{5}{9}\right)+\frac{1}{12}=\frac{1}{90}\)
b) \(\left(7-\frac{4}{3}+\frac{1}{3}\right)-\left(6+\frac{5}{4}-\frac{4}{3}\right)-\left(5-\frac{7}{4}+\frac{5}{3}\right)\)
Bài 3 : Tính:
a, A = \(\frac{2}{5}+\frac{-1}{6}-\frac{3}{4}-\frac{-2}{3}\)
b, B = \(\frac{7}{10}-\frac{-3}{4}+\frac{-5}{6}-\frac{1}{5}+\frac{-2}{3}\)
c, C = \(\frac{\left(\frac{1}{2}-0,75\right)\times\left(0,2-\frac{2}{5}\right)}{\frac{5}{9}-1\frac{1}{12}}\)
d, D = \(\frac{\frac{2}{3}+\frac{2}{7}-\frac{1}{4}}{-1-\frac{3}{7}+\frac{3}{28}}\)
tính nhanh
a, \(\frac{7}{12}.\frac{6}{11}+\frac{7}{12}.\frac{5}{11}-2\frac{7}{12}\)
b,\(\frac{-5}{9}.\frac{-6}{13}+\frac{5}{-9}.\frac{-5}{13}-\frac{5}{9}\)
c,\(0,8.\frac{-15}{14}-\frac{4}{5}.\frac{13}{14}-1\frac{2}{5}\)
d, \(75\%.\frac{6}{7}+5\%.\frac{6}{7}+\frac{7}{10}.1\frac{1}{7}\)
tính nhanh
a, \(\frac{7}{12}.\frac{6}{11}+\frac{7}{12}.\frac{5}{11}-2\frac{7}{12}\)
b,\(\frac{-5}{9}.\frac{-6}{13}+\frac{5}{-9}.\frac{-5}{13}-\frac{5}{9}\)
c, \(0,8.\frac{-15}{14}-\frac{4}{5}.\frac{13}{14}-1\frac{2}{5}\)
d,\(75\%.\frac{6}{7}+5\%.\frac{6}{7}+\frac{7}{10}.1\frac{1}{7}\)
Tính:
1,\(\frac{2}{5}+\left(-\frac{4}{5}\right)+\left(-\frac{1}{2}\right)\)
2,\(A=\frac{0,375-0,3+\frac{3}{11}+\frac{3}{12}}{-0,625+0,5-\frac{5}{11}-\frac{5}{12}}+\frac{1,5+1-0,75}{2,5+\frac{5}{3}-1,25}\)
3,\(B=\frac{\frac{1}{3}-\frac{1}{7}-\frac{1}{13}}{\frac{2}{3}-\frac{2}{7}-\frac{2}{13}}.\frac{\frac{1}{3}-0,25+0,2}{1\frac{1}{6}-0,875+0,7}+\frac{6}{7}\)