B1a)\(11\frac34-\left(6\frac56-4\frac12\right)+1\frac23\)

=\(11\frac34-6\frac56+4\frac12+1\frac23\)

=\(\left(11-6+4+1\right)+\left(\frac34-\frac56+\frac12+\frac23\right)\)

=\(10+\left(\frac{9}{12}-\frac{10}{12}+\frac{6}{12}+\frac{8}{12}\right)\)

=\(10+\left(-\frac{1}{12}+\frac{6}{12}+\frac{8}{12}\right)\)

=10+\(\frac{13}{12}\)

=\(\frac{120}{12}+\frac{13}{12}\)

=\(\frac{133}{12}\)

b)\(2\frac{17}{20}-1\frac{11}{5}+6\frac{9}{20}:3\)

= \(\frac{57}{20}-\frac{16}{5}+\frac{129}{20}\times\frac13\)

=\(\frac{57}{20}-\frac{16}{5}+\frac{129}{60}\)

=\(\frac{171}{60}-\frac{192}{60}+\frac{129}{60}\)

=\(\frac{108}{60}\)

=\(\frac95\)

Câu 1:

A = (4/9 + 5/6) : (7/8 - 7/12)

A = (8/18 + 15/18) :(21/24 - 14/24)

A = 23/18 : 7/24

A = 23/18 x 24/7

A = 92/21

Câu B = 3/4.8/9.15/16...9999/10000

B = \(\frac{1.3}{2.2}\).\(\frac{2.4}{3.3}\)....\(\frac{99.101}{100.100}\)

B = \(\frac{1.2.3\ldots99}{2.3\ldots100}\). \(\frac{3.4.\ldots101}{2.3\ldots100}\)

B = \(\frac{1}{100}\) x \(\frac{101}{2}\)

B = \(\frac{101}{200}\)

a,\(\frac{31}{1000}\)

b,\(\frac{8}{108}\)

c,0

a,\(\frac{49}{97}\)

b,\(\frac{-1}{4751}\)

a) \(2^3+3.\left(\frac{1}{2}\right)^0+\left[\left(-2\right)^2:\frac{1}{2}\right]\)

\(=8+3.1+4:\frac{1}{2}\)

\(=8+3+8=19\)

b)\(\frac{2^{15}.9^4}{6^6.8^3}=\frac{2^{15}.\left(3^2\right)^4}{\left(2.3\right)^6.\left(2^3\right)^3}=\frac{2^{15}.3^8}{2^6.3^6.2^9}\)\(=\frac{2^{15}.3^8}{2^{15}.3^6}=3^2=9\)

c) \(\left(1+\frac{2}{3}-\frac{1}{4}\right).\left(\frac{4}{5}-\frac{3}{4}\right)^2\)

\(=\frac{17}{12}.\frac{1}{400}=\frac{17}{4800}\)

d) \(\left(-\frac{10}{3}\right)^3.\left(\frac{-6}{5}\right)^4=-\frac{100}{27}.\frac{1296}{625}\)\(=\frac{-4.48}{1.25}=-\frac{192}{25}\)

\(\left(\frac{3}{8}+-\frac{3}{4}+\frac{7}{12}\right):\frac{5}{6}+\frac{1}{2}\)

\(=\left(\frac{9}{24}+-\frac{18}{24}+\frac{14}{24}\right):\frac{5}{6}+\frac{1}{2}\)

\(=\frac{5}{24}:\frac{5}{6}+\frac{1}{2}\)

\(=\frac{5}{24}.\frac{6}{5}+\frac{1}{2}\)

\(=\frac{1}{4}+\frac{1}{2}\)

\(=\frac{1}{4}+\frac{2}{4}\)

\(=\frac{3}{4}\)

\(\frac{1}{2}+\frac{3}{4}-\left(\frac{3}{4}-\frac{4}{5}\right)\)

\(=\frac{1}{2}+\frac{3}{4}-\left(\frac{15}{20}-\frac{16}{20}\right)\)

\(=\frac{1}{2}+\frac{3}{4}-\frac{-1}{20}\)

\(=\frac{10}{20}+\frac{15}{20}-\frac{-1}{20}\)

\(=\frac{25}{20}-\frac{-1}{20}\)

\(=\frac{26}{20}\)

\(=\frac{13}{10}\)

a) \(\left(2\frac{5}{6}+1\frac{4}{9}\right):\left(10\frac{1}{12}-9\frac{1}{2}\right)\)

\(=\left(\frac{17}{6}+\frac{13}{9}\right):\left(\frac{121}{12}-\frac{19}{2}\right)\)

\(=\frac{77}{18}:\frac{7}{12}\)

\(=\frac{22}{3}\)

b) \(1\frac{5}{18}-\frac{5}{18}.\left(\frac{1}{15}+1\frac{1}{12}\right)\)

\(=\frac{23}{18}-\frac{5}{18}.\left(\frac{1}{15}+\frac{13}{12}\right)\)

\(=\frac{23}{18}-\frac{5}{18}.\frac{23}{20}\)

\(=\frac{23}{18}-\frac{23}{72}\)

\(=\frac{23}{24}\)

c) \(-1\frac{1}{7}.\left(9\frac{1}{2}-8,75\right):\frac{2}{7}+0,625:1\frac{2}{3}\)

\(=\frac{-8}{7}.\left(\frac{19}{2}-\frac{35}{4}\right):\frac{2}{7}+\frac{5}{8}:\frac{5}{3}\)

\(=\frac{-8}{7}.\frac{3}{4}:\frac{2}{7}+\frac{3}{8}\)

\(=\frac{-8}{7}.\frac{3}{4}.\frac{7}{2}+\frac{3}{8}\)

\(=-3+\frac{3}{8}\)

\(=\frac{-21}{8}\)

Chúc bn học tốt !!

\(a.=\left(\frac{153}{37}-\frac{19}{5}+\frac{199}{23}\right)-\left(\frac{116}{37}-\frac{188}{29}\right)\)

\(=\frac{153}{37}-\frac{19}{5}+\frac{199}{23}-\frac{116}{37}+\frac{188}{29}\)

\(=\frac{37}{37}-\frac{19}{5}+\frac{199}{23}+\frac{188}{29}\)tự giải tiếp ^^

\(b.=\frac{8}{3}.\frac{-15}{4}.\frac{4}{5}\)

\(=\frac{8.\left(-15\right).4}{3.4.5}\)

\(=\frac{-480}{60}=-8\)

thank u vẻ rỳ much