Tính hợp lí:
a, 75. ( \(-2\frac{3}{25}+7\frac{2}{75}-5\frac{4}{15}\) )
b, \(45.\left(5\frac{4}{15}-4\frac{7}{9}-1\frac{8}{45}\right)\)
c, \(\frac{-5}{8}+\frac{14}{18}-\frac{3}{8}+\frac{2}{9}-\frac{1}{2006}\)
d, \(\frac{15}{29}-\frac{8}{7}+\frac{16}{14}+\frac{14}{29}-\frac{3}{8}\)
e, \(\frac{1}{3.5}+\frac{1}{5.7}+...+\frac{1}{49.51}\)
\(a,1\frac{13}{15}.0,75-\left(\frac{8}{15}+0,25\right).\frac{24}{47}\)
\(b,5:\left(4\frac{3}{4}-1\frac{25}{28}\right)-1\frac{3}{8}:\left(\frac{3}{8}+\frac{9}{20}\right)\)
\(c,6\frac{5}{12}:2\frac{3}{4}+11\frac{1}{4}.\left(\frac{1}{3}-\frac{1}{5}\right)\)
\(d,\left(\frac{3}{5}+0,415-\frac{3}{200}\right).2\frac{2}{3}.0,25\)
\(e,\left(\frac{3}{8}+\frac{-3}{4}+\frac{7}{12}\right):\frac{5}{6}+\frac{1}{2}\)
\(g,1\frac{13}{15}.0,75-\left(\frac{11}{20}+25\%\right);\frac{7}{3}\)
1.Thực hiện phép tính:
a) 45 : \(2\frac{4}{7}+50\)o/o - 1,25
b) \(4\frac{2}{5}.0,5-1\frac{3}{7}.14\)o/o + (-0,8)
c) \(1\frac{3}{8}+\frac{1}{8}:\)(75o/o - \(\frac{1}{2}\)) - 25o/o . \(\frac{1}{2}\)
d) 75o/o + 18 + 1,25 . \(\frac{4}{5}-18\frac{3}{4}\)
2.THPT:
A = \(\frac{9}{1.2}+\frac{9}{2.3}+\frac{9}{3.4}+...+\frac{9}{98.99}+\frac{9}{99.100}\)
B = \(\frac{2}{5.7}+\frac{2}{7.9}+\frac{2}{9.11}+...+\frac{2}{93.95}\)
C = \(\left(1-\frac{1000}{2017}\right).\left(1-\frac{1001}{2017}\right)...\left(1-\frac{2017}{2018}\right)\)
D = \(\frac{5}{2.7}+\frac{4}{7.11}+\frac{3}{11.14}+\frac{1}{14.15}+\frac{13}{15.28}\)
3. Tìm x:
a)\(\left(2\frac{4}{5}x-50\right):\frac{2}{3}=51\)
b) \(3\frac{1}{3}x+16\frac{3}{4}=-13,25\)
c) \(\frac{2}{3}x-\frac{5}{6}x=\frac{11}{24}\)
d) x + \(\frac{2}{5}x=\frac{-14}{55}\)
e) \(\frac{2}{5}x-x=\frac{\left(-2018\right)^0}{5^2}\)
f) x + \(\left(x+\frac{2}{7}\right)+\frac{-5}{11}=\frac{4}{11}\)
Help me!!!!!!
\(\left(20+9\frac{1}{4}\right):2\frac{1}{4}\) \(\left(6-2\frac{4}{5}\right).3\frac{1}{8}-1\frac{3}{5}:\frac{1}{4}\)
\(\frac{32}{15}:\left(-1\frac{1}{5}+1\frac{1}{3}\right)\) \(0,2.\frac{15}{36}-\left(\frac{2}{5}=\frac{2}{3}\right):1\frac{1}{5}\)
\(\frac{-3}{7}.\frac{5}{9}+\frac{4}{9}.\frac{-3}{7}+2\frac{3}{7}\) \(0,7.2\frac{2}{3}.20.0,375.\frac{5}{8}\)
2,Thực hiện phép tính(tính nhanh nếu có thể)
a,\(\frac{2}{3}+\frac{1}{3}\cdot\left(-\frac{2}{5}\right)\)
b,\(0,75\cdot1\frac{7}{9}-1\frac{2}{5}:\frac{-21}{20}\)
c,\(\frac{-2}{17}+\frac{15}{23}+\frac{15}{-17}-\frac{-4}{19}+\frac{8}{23}\)
d,\(2019^0\cdot\left(6-2\frac{4}{5}\right)\cdot3\frac{1}{8}-1\frac{3}{5}:25\)phần trăm
e,\(\left(\frac{7}{8}-\frac{1}{2}\right)\cdot2\frac{2}{3}-\frac{3}{7}\cdot\left(2,5^2\right)\)
Tính hợp lí :
\(\frac{1}{7}.\frac{1}{3}+\frac{1}{7}.\frac{1}{2}-\frac{1}{7}\)
Rút gọn rồi tính :
1) \(\frac{5^4\times9^5}{15^3\times27^3}\)
2) \(\frac{8^8\times3^{14}}{9^6\times2^{20}}\)
3) \(\frac{4^{10}\times25^7}{5^{14}\times8^6}\)
4) \(\frac{25^7\times2^{15}}{8^5\times5^{12}}\)
\(a,\frac{16}{15}\cdot\frac{-5}{14}\cdot\frac{54}{24}\cdot\frac{56}{21}\)
\(b,5\cdot\frac{7}{5}\) \(c,\frac{1}{7}\cdot\frac{5}{9}+\frac{5}{9}\cdot\frac{1}{7}+\frac{5}{9}\cdot\frac{3}{7}\)
\(d,4\cdot11\cdot\frac{3}{4}\cdot\frac{9}{121}\)
\(e,\frac{3}{4}\cdot\frac{16}{9}-\frac{7}{5}:\frac{-21}{20}\)
\(g,2\frac{1}{3}-\frac{1}{3}\cdot\left[\frac{-3}{2}+\left(\frac{2}{3}+0,4\cdot5\right)\right]\)
\(a,\left(9,75.21\frac{3}{7}+\frac{39}{4}.18\frac{4}{7}\right).\frac{15}{78}\)
\(b,\frac{-7}{21}+\left(1+\frac{1}{3}\right)\) \(c,\frac{2}{15}+\left(\frac{5}{9}+\frac{-6}{9}\right)\)
\(d,\left(\frac{-1}{5}+\frac{3}{12}\right)+\frac{-3}{4}\)
\(e,\frac{4}{20}+\frac{16}{42}+\frac{6}{15}+\frac{-3}{5}+\frac{2}{21}+\frac{-10}{21}+\frac{3}{20}\)
Bài 1: Tính (hợp lý nếu có thể)
a) \(\frac{8}{40}+\frac{-4}{20}-\frac{3}{5}\)
b) \(\frac{-7}{12}+\frac{-2}{12}-\frac{-3}{36}\)
c) \((\frac{1}{6}+\frac{-4}{13})-(\frac{-17}{6}-\frac{30}{13})\)
d) \(-\frac{-5}{4}+\frac{7}{4}-\frac{-11}{7}+\frac{2}{7}\)
e) \(-\frac{1}{8}+\frac{-7}{9}+\frac{-7}{8}+\frac{6}{7}+\frac{2}{14}\)
f) \(\frac{-2}{9}-\frac{11}{-9}+\frac{5}{7}-\frac{-6}{-7}\)
1.tính các biểu thức sau bằng một cách hợp lí
a.\(\frac{108}{119}.\frac{107}{211}+\frac{108}{119}.\frac{104}{211}\)
b.\(\frac{15}{19}.\frac{27}{33}+\frac{15}{19}.\frac{19}{33}-\frac{15}{19}.\frac{13}{33}\)
c.\(\frac{-4}{5}.\frac{13}{10}+\frac{-4}{5}.\frac{7}{10}-\frac{-4}{5}\)
d.\(\frac{\frac{-2}{7}-\frac{-2}{15}+\frac{-2}{39}}{\frac{5}{7}-\frac{5}{15}+\frac{5}{39}}\)
e.\(\frac{3}{5}.\frac{15}{7}-\frac{15}{7}.\frac{8}{5}\)
f.\(\frac{2}{3}+\frac{1}{3}.\left(\frac{-4}{9}+\frac{5}{6}\right):\frac{7}{12}\)
h.\(\frac{\frac{3}{5}+\frac{3}{7}-\frac{3}{11}}{\frac{4}{5}+\frac{4}{7}-\frac{4}{11}}\)
g.\(\frac{3}{-4}+\frac{2}{7}+\frac{-1}{4}+\frac{5}{7}+\frac{21}{22}.\frac{66}{7}\)
k.\(\frac{27.18+27.103-120.27}{15.33+33.12}\)
l.\(\frac{\frac{2}{5}+\frac{2}{7}-\frac{2}{9}-\frac{2}{11}}{\frac{4}{5}+\frac{4}{7}-\frac{4}{9}-\frac{4}{11}}\)