\(\frac{45}{78}+\frac{72}{88}+\frac{93}{55}\)
=\(\frac{15}{26}+\frac{9}{11}+\frac{93}{55}\)
=\(\frac{15}{26}+\frac{138}{55}\)
=\(\frac{4413}{1430}\)
Tính nhanh
\(A=\frac{1}{2}+\frac{5}{6}+\frac{11}{12}+\frac{19}{20}+\frac{29}{30}+\frac{41}{42}+\frac{55}{56}+\frac{71}{72}+\frac{89}{90}\)
A=\(\frac{10-\frac{1}{9}-\frac{2}{10}-\frac{3}{11}-...-\frac{10}{18}}{\frac{1}{45}+\frac{1}{50}+\frac{1}{55}+...+\frac{1}{90}}\)
Tìm x biết: \(\frac{55-x}{1963}+\frac{50-x}{1968}+\frac{45-x}{1973}+\frac{40-x}{1978}+4=0\)
1 * 2 * 3 * 4 * 5 * 6 * 7 * 8 * 9 * 10 * 11 * 12 * 13 * 14 * 15 * 16 * 17 * 18 * 19 * 20 * 21 * 22 * 23 * 24 * 25 * 26 * 27 * 28 * 29 * 30 * 31 * 32 * 33 * 34 * 35 * 36 * 37 * 38 * 39 * 40 * 41 * 42 * 43 * 44 * 45 * 46 * 47 * 48 * 49 * 50 * 51 * 52 * 53 * 54 * 55 * 56 * 57 * 58 * 59 * 60 * 61 * 62 * 63 * 64 * 65 * 66 * 67 * 68 * 69 * 70 * 71 * 72 * 73 * 74 * 75 * 76 * 77 * 78 * 79 * 80 * 81 * 82 * 83 * 84 * 85 * 86 * 87 * 88 * 89 * 90 * 91 * 92 * 93 * 94 * 95 * 96 * 97 * 98 * 99 * 100 bằng bao nhiêu?
Tìm x biết:
a)\(\frac{x-1}{21}=\frac{3}{x+1}\)
b)\(\frac{7}{x}+\frac{4}{5.9}+\frac{4}{9.13}+\frac{4}{13.17}+...+\)\(\frac{4}{41.45}=\frac{29}{45}\)
c)\(\frac{1}{3.5}+\frac{1}{5.7}+\frac{1}{7.9}+...+\)\(\frac{1}{\left(2x+1\right).\left(2x+3\right)}=\frac{15}{93}\)
\(\frac{59-x}{41}\)+ \(\frac{57-x}{43}\)+ \(\frac{55-x}{45}\)+ \(\frac{53-x}{47}\)+ \(\frac{51-x}{49}\)= -5
Tìm x biết :
a/\(\frac{x+1945}{45}+\frac{x+1954}{54}\)=\(\frac{x+1975}{75}+\frac{x+1969}{69}\)
b/\(\frac{x-99}{5}+\frac{x-97}{7}\)=\(\frac{x-95}{9}+\frac{x-93}{11}\)
c/\(\frac{x+2008}{10}+\frac{x+2010}{9}\)=\(\frac{x+2012}{8}+\frac{x+2014}{7}\)
Cho \(P=\frac{\frac{1}{99}+\frac{2}{98}+\frac{3}{97}+..+\frac{99}{1}}{\frac{1}{2}+\frac{1}{3}+\frac{1}{4}+..+\frac{1}{100}}\)và \(Q=\frac{92-\frac{1}{9}-\frac{2}{10}-\frac{3}{11}-..-\frac{92}{100}}{\frac{1}{45}+\frac{1}{50}+\frac{1}{55}+..+\frac{1}{500}}\)
a)Tính P,Q b) Tính tỉ số % của P và 3Q
Cho \(M=\frac{\frac{1}{99}+\frac{2}{98}+\frac{3}{97}+.......+\frac{99}{1}}{\frac{1}{2}+\frac{1}{3}+\frac{1}{4}....+\frac{1}{100}}\)
\(N=\frac{92-\frac{1}{9}-\frac{2}{10}-\frac{3}{11}-....-\frac{92}{100}}{\frac{1}{45}+\frac{1}{50}+\frac{1}{55}+.....+\frac{1}{495}+\frac{1}{500}}\)
Tính M; N
