Tính thuận tiện
a) \(1\frac{1}{2}\times1\frac{1}{3}\times1\frac{1}{4}\times...\times1\frac{1}{2014}\)
b) \(1\frac{1}{3}\times1\frac{1}{8}\times1\frac{1}{15}\times...\times1\frac{1}{99}\)
c) \(\frac{1x2+2x4+3x6+4x8+5x10}{1x3+2x6+3x9+4x12+5x15}\)
d) \(\frac{1}{10}+\frac{4}{20}+\frac{9}{30}+\frac{16}{40}+\frac{25}{50}+\frac{36}{40}+\frac{49}{70}+\frac{64}{80}+\frac{81}{90}\)
e)\(\frac{10}{20}x\frac{2020}{3030}x\frac{303030}{404040}x...x\frac{808080...80}{909090...90}\) f)\(\frac{100x100-1}{99x101}\)
g) \(\frac{1-\frac{2}{25}+\frac{5}{6}+\frac{3}{4}}{2-\frac{4}{25}+\frac{5}{3}+\frac{3}{2}}\)
a, \(\frac{3}{2}.\frac{4}{3}.\frac{5}{4}......\frac{2015}{2014}=\frac{3.4.5.....2015}{2.3.4....2014}\)
\(=\frac{2015}{2}=1007\frac{1}{2}\)
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