3

5

6

25

6:2=3

25:5=5

2x3=6

5x5=25

6:2=3

25:5=5

2*3=6

5*5=25

5×5-6+8=25-6+8=19+8=27

8×4×1=32×1=32

5x5-6=8 = 27

8x4x1 = 32

27

32 

tik mk mk tik lại

bằng 0

= 5 nhé bạn

lm j có phép chia nào chia cho 0 đâu bn

\(\frac{7}{9}\times\frac{3}{5}+\frac{3}{5}\times\frac{5}{6}+\frac{3}{5}\times1\)

\(=\frac{3}{5}\times\left(\frac{7}{9}+\frac{5}{6}+1\right)\)

\(=\frac{3}{5}\times\frac{47}{18}\)

\(=\frac{47}{30}\)

 #hoktot<3# 

máy tính hoặc não

a: =9/11(7/4+5/4)=9/11x3=27/11

b: \(=\dfrac{28}{5}\cdot\dfrac{5}{8}\cdot\dfrac{5}{4}=\dfrac{28}{8}\cdot\dfrac{5}{4}=\dfrac{140}{32}=\dfrac{35}{8}\)

c: \(=\dfrac{2}{6}+\dfrac{4}{5}\cdot\dfrac{6}{5}-\dfrac{2}{5}=\dfrac{67}{75}\)

a,=(7/4+5/4):11/9

=3:11/9

=27/11

b,=28/5.5/4.5/8

=7.5/8

=35/8

c,=1/3+24/25-2/5

=97/75-2/5

=67/75

7/4:11/9+5/4:11/9

=7/4×9/11+5/4×9/11

=9/11×(7/4+5/4)

=9/11×12/4

=9/11×3

=27/11

b)

28/5:4/5×5/8

=28/5×5/4×5/8

=28/4×5/8

=7×5/8

=35/8

c)

2/3×3/6+4/5:5/6−2/5

=2/6+4/5×6/5−2/5

=1/3+24/25−2/5

=(24/25−2/5)+1/3

=14/25+1/3

=67/75

a) = 29/5

b) = 1/10

c) = 1/2

d) ?

a) \(\dfrac{12}{15}+5=\dfrac{4}{5}+5=\dfrac{4}{5}+\dfrac{25}{5}=\dfrac{29}{5}\)

b) \(\dfrac{7}{10}-\dfrac{6}{10}=\dfrac{1}{10}\)

c) \(\dfrac{3}{5}x\dfrac{5}{6}=\dfrac{15}{30}=\dfrac{1}{2}\)

d) lỗi 

a) \(\dfrac{12}{15}+5=\dfrac{4}{5}+5=\dfrac{4}{5}+\dfrac{5}{1}=\dfrac{4}{5}+\dfrac{25}{5}=\dfrac{29}{5}\)

b) \(\dfrac{7}{10}-\dfrac{3}{5}=\dfrac{7}{10}-\dfrac{6}{10}=\dfrac{1}{10}\)

c) \(\dfrac{3}{5}\times\dfrac{5}{6}=\dfrac{3\times5}{5\times6}=\dfrac{15}{30}=\dfrac{1}{2}\)

d) Thiếu số

6x6=30

Như vậy thì 6.6=30

3X3-3=6

4X4-4=12

5X5-5=20

6X6-6=30

ĐS: 30

Chắc câu hỏi khó quá các AE ko nói đ thôi hỏi lớp 3 câu này vậy