8

5

10

10

10

8

5

10

10

10

8

5

10

10

10

1.2.3.4...9=362880

1 . 2 . 3 . 4 . 5 . 6 . 7 . 8 . 9

362880

77/45

7/6

29/10

\(\dfrac{3}{5}+\dfrac{4}{3}\times\dfrac{5}{6}=\dfrac{3}{5}+\dfrac{10}{9}=\dfrac{27}{45}+\dfrac{50}{45}=\dfrac{77}{45}\)

\(2-\dfrac{7}{6}+\dfrac{1}{3}=\dfrac{12}{6}-\dfrac{7}{6}+\dfrac{2}{6}=\dfrac{7}{6}\)

\(\dfrac{7}{6}\times3-\dfrac{3}{5}=\dfrac{7}{2}-\dfrac{3}{5}=\dfrac{35}{10}-\dfrac{6}{10}=\dfrac{29}{10}\)

giải chi tiết đi

=[5+5]+[1+9]+[6+4]+[7+3]+8

=10+10+10+10+8

=20+20+8

=40+8

=48

=(5+5)+(1+9)+(6+4)+(7+3)+(8+4)+10:2

=10+10+10+10+12+10:2

=62:2=31

a) 1/7 + 2/7 + 3/7 + 4/7 + 5/7 +6/7 = 3

b) 1/2 + 2/4 + 3/6 + 4/8 + 5/10 + 6/12 = 3

câu a bằng 3 nha
câu b cũng bằng 3 nha

a,\(\frac{1}{7}+\frac{2}{7}+\frac{3}{7}+\frac{4}{7}+\frac{5}{7}+\frac{6}{7}=\frac{1+2+3+4+5+6}{7}\)\(=\)\(\frac{21}{7}\)

b,\(\frac{1}{2}+\frac{2}{4}+\frac{3}{6}+\frac{4}{8}+\frac{5}{10}+\frac{6}{12}\)\(=\)\(\frac{1}{2}+\frac{1}{2}+\frac{1}{2}+\frac{1}{2}+\frac{1}{2}+\frac{1}{2}\)\(=\)\(\frac{1+1+1+1+1+1}{2}\)\(=\)\(\frac{6}{2}=6\div2=3\)

        \(\dfrac{5}{6}\) + \(\dfrac{7}{8}\)

=     \(\dfrac{5\times4}{6\times4}\) + \(\dfrac{7\times3}{8\times3}\)

=      \(\dfrac{20}{24}\) + \(\dfrac{21}{24}\)

=         \(\dfrac{41}{24}\)

5/6 + 7/8 = 41/24

2 + 2/3 = 8/3

7/9 - 1/7 = 40/63

1-1/11 =10/11

2x17/81 = 34/81

9/11 : 5/6 = 54/55

3: 12/25 = 25/4

                Tick cho mik nhé.

       Chúc bạn học tốt nha !

2 + \(\dfrac{2}{3}\)

= \(\dfrac{2\times3}{1\times3}\) +  \(\dfrac{2}{3}\)

= \(\dfrac{6}{3}\) + \(\dfrac{2}{3}\)

= \(\dfrac{8}{3}\)

= 1192 nhé

 hok tốt

:D