a) \(\frac{59}{42}\)
b) \(\frac{17}{36}\)
c) \(\frac{5}{51}\)
d) \(\frac{4}{7}\)

a: \(\frac56+\frac47=\frac{35}{42}+\frac{24}{42}=\frac{35+24}{42}=\frac{59}{42}\)

b: \(\frac54-\frac79=\frac{45}{36}-\frac{28}{36}=\frac{45-28}{36}=\frac{17}{36}\)

c: \(\frac{15}{17}\times\frac19=\frac{15\times1}{17\times9}=\frac{15}{153}=\frac{5}{51}\)

d: \(\frac37:\frac68=\frac37:\frac34=\frac37\times\frac43=\frac47\)

a,(11/15+4/15)+(5/7+2/7)

=1+1

=2

b,5/9x(1/2+6/4)

=5/9x2

=10/9

c,1/2:(7/8+9/8)

=1/2:2

=1

d,(17/10-7/10)+1/2

=1+1/2

=3/2

a) \(\frac{11}{15}+\frac{5}{7}+\frac{2}{7}+\frac{4}{15}=\left(\frac{11}{15}+\frac{4}{15}\right)+\left(\frac{5}{7}+\frac{2}{7}\right)\)

\(=2\)

b) \(\frac{5}{9}\times\frac{1}{2}\times\frac{5}{9}\times\frac{6}{4}=\frac{25}{81}\times\frac{3}{4}=\frac{25}{108}\)

c) \(\frac{7}{8}\div\frac{1}{2}+\frac{9}{8}\div\frac{1}{2}=\left(\frac{7}{8}+\frac{9}{8}\right)\div\frac{1}{2}\)

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

d) \(\frac{17}{10}+\frac{1}{2}-\frac{7}{10}=\left(\frac{17}{10}-\frac{7}{10}\right)+\frac{1}{2}\)

\(=1+\frac{1}{2}=\frac{3}{2}\)

a) \(\frac{11}{15}+\frac{5}{7}+\frac{2}{7}+\frac{4}{15}\)

\(=\left(\frac{11}{15}+\frac{4}{15}\right)+\left(\frac{5}{7}+\frac{2}{7}\right)\)

\(=1+1\)

\(=2\)

b) \(\frac{5}{9}.\frac{1}{2}.\frac{5}{9}.\frac{6}{4}\)

\(=\left(\frac{5}{9}\right)^2\left(\frac{1}{2}.\frac{6}{4}\right)\)

\(=\frac{25}{81}.\frac{3}{4}\)

\(=\frac{25}{108}\)

c) \(\frac{7}{8}:\frac{1}{2}+\frac{9}{8}:\frac{1}{2}\)

\(=\frac{7}{8}.2+\frac{9}{8}.2\)

\(=2\left(\frac{7}{8}+\frac{9}{8}\right)\)

\(=2.\frac{16}{8}\)

\(=2.2\)

\(=4\)

d) \(\frac{17}{10}+\frac{1}{2}-\frac{7}{10}\)

\(=\left(\frac{17}{10}-\frac{7}{10}\right)+\frac{1}{2}\)

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

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

\(=\frac{3}{2}\)

a ) (11/15+4/15 ) + ( 5/7 +2 /7 )

=1+1

= 2

b)5/9 x ( 1/ 2 + 6/ 4 )

= 5/9 x 2

=10/9 

c) 17/10-5/10-7/10

=(17-5-7) / 10

= 5/10

\(\frac{11}{9}-\frac67\)

\(=\frac{77}{63}-\frac{54}{63}=\frac{77-54}{63}=\frac{23}{63}\)

\(\frac{7}{10}-\frac25=\frac{7}{10}-\frac{4}{10}=\frac{7-4}{10}=\frac{3}{10}\)

\(\frac72-2=\frac72-\frac42=\frac{7-4}{2}=\frac32\)

\(\frac65\times\frac38=\frac{6\times3}{5\times8}=\frac{18}{40}=\frac{9}{20}\)

\(\frac25:\frac32=\frac25\times\frac23=\frac{2\times2}{5\times3}=\frac{4}{15}\)

\(5:\frac57=5\times\frac75=7\)

\(\frac73:4=\frac{7}{3\times4}=\frac{7}{12}\)

911​−76​

\(= \frac{77}{63} - \frac{54}{63} = \frac{77 - 54}{63} = \frac{23}{63}\)

\(\frac{7}{10} - \frac{2}{5} = \frac{7}{10} - \frac{4}{10} = \frac{7 - 4}{10} = \frac{3}{10}\)

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

\(\frac{6}{5} \times \frac{3}{8} = \frac{6 \times 3}{5 \times 8} = \frac{18}{40} = \frac{9}{20}\)

\(\frac{2}{5} : \frac{3}{2} = \frac{2}{5} \times \frac{2}{3} = \frac{2 \times 2}{5 \times 3} = \frac{4}{15}\)

\(5 : \frac{5}{7} = 5 \times \frac{7}{5} = 7\)

\(\frac{7}{3} : 4 = \frac{7}{3 \times 4} = \frac{7}{12}\)

Giúp mình nhanh nha

a: \(\frac79-\frac{4}{15}+\frac61\)

\(=\frac{35}{45}-\frac{12}{45}+6\)

\(=6+\frac{23}{45}=\frac{270}{45}+\frac{23}{45}=\frac{293}{45}\)

b: \(\frac{44}{21}-\left(\frac34+\frac{2}{21}\right)\)

\(=\frac{44}{21}-\frac{2}{21}-\frac34\)

\(=2-\frac34=\frac54\)

c: \(\frac{17}{12}+\frac{13}{7}-\frac67+\frac{7}{12}\)

\(=\frac{17}{12}+\frac{7}{12}+\left(\frac{13}{7}-\frac67\right)\)

=2+1

=3

1) \(4\frac{3}{10}=\frac{43}{10};21\frac{7}{100}=\frac{2107}{100};7\frac{39}{100}=\frac{739}{100};6\frac{123}{1000}=\frac{6123}{1000}\)

2)\(a,5\frac{2}{10}+7\frac{1}{10}=\frac{52}{10}+\frac{71}{10}=\frac{123}{10}\)

\(b,5\frac{6}{7}-3\frac{5}{7}=\frac{41}{7}-\frac{26}{7}=\frac{15}{7}\)

\(c,8\frac{3}{5}x2\frac{6}{7}=\frac{43}{5}x\frac{20}{7}=\frac{172}{7}\)

\(d,1\frac{3}{10}:5\frac{7}{8}=\frac{13}{10}:\frac{47}{8}=\frac{13}{10}x\frac{47}{8}=\frac{611}{80}\)

3) \(7\frac{9}{10}và4\frac{9}{10}\)

Ta có: \(7\frac{9}{10}=\frac{79}{10};4\frac{9}{10}=\frac{49}{10}\)

Suy ra: \(\frac{79}{10}>\frac{49}{10}hay7\frac{9}{10}>4\frac{9}{10}\)

 \(6\frac{3}{10}và6\frac{5}{9}\)

Ta có: \(6\frac{3}{10}=\frac{63}{10};6\frac{5}{9}=\frac{59}{9}\)

Suy ra: \(\frac{63}{10}>\frac{59}{9}hay6\frac{3}{10}>6\frac{5}{9}\)

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