Tính:3/7 4 = .............................................5/9 x 3 = .............................................7/8 - 2/9 = ..........................................5 - 3/4 = ........................

2

VQ

Vũ Quang Huy

14 tháng 4 2022

3/7 + 4 = 3/7 + 4/1 = 31/7

5/9 x 3 =5/9 x 3/1 = 15/9 = 5/3

7/8 - 2/9 =7/8 - 2/9 =47/72

5 - 3/4 =5/1 - 3/4 = 20/4 - 3/4 = 17/4

5/7 : 6 = 5/7 : 6/1 = 5/7 x 1/6 = 5/42

5/6 x 2/7 =10/42= 5/21

3 + 3/4 = 3/1 + 3/4 = 12/4+ 3/4 =15/4

3/5 x 4/8 =12/40 = 3/10.

5 : 3/8 = 5/1 : 3/8 = 5/1 x 8/5 = 8/1= 8

3 x 5/9 =3/1 x 5/9 = 15/9=5/3

HN

Hoàng Ngân Hà

14 tháng 4 2022

Thanks kiu my friend

Đúng(1)

PT

Pham Trong Bach

13 tháng 4 2019

Tính nhẩm

3 x 4 = 2 x 6 = 4 x 3 = 5 x 6 =

3 x 7 = 2 x 8 = 4 x 7 = 5 x 4 =

3 x 5 = 2 x 4 = 4 x 9 = 5 x 7 =

3 x 8 = 2 x 9 = 4 x 4 = 5 x 9 =

#Toán lớp 3

4

CM

Cao Minh Tâm

13 tháng 4 2019

Học sinh nhẩm và ghi kết quả như sau:

3 x 4 = 12 2 x 6 = 12 4 x 3 = 12 5 x 6 = 30

3 x 7 = 21 2 x 8 = 16 4 x 7 = 28 5 x 4 = 20

3 x 5 = 15 2 x 4 = 8 4 x 9 = 36 5 x 7 = 35

3 x 8 = 24 2 x 9 = 18 4 x 4 = 16 5 x 9 = 45

MH

Mỹ Hằng Nguyễn Thị

6 tháng 9 2021

3 x4 = 12

3 x7 = 21

3 x5 = 15

3 x8 =24

2 x 6= 12

2 x8 = 16

2 x4 =8

2 x9 =18

4 x3 =12

4 x7 =28

4 x9 =36

4 x4 =16

5 x6 =30

5 x4 =20

5 x7 =35

5 x9 =45

NP

Nguyễn Phương Anh

19 tháng 3 2023

Tính 9/5 + 3/4 4/7 x 3/8 6/7 x 2/3 - 2/7 3/5 - 2/9 5/9 ÷ 5/6 4/5 ÷2/5 x 1/4

Nhanh giúp mik nhá

2

HT

Hoàng Thị Thu Phúc

19 tháng 3 2023

= 51/20

----------------------------------

= 3/14

------------------------------------

= 4/7 - 2/7

= 2/7

--------------------------------------

= 17/45

---------------------------------------

= 2/3

--------------------------------------

= 2 x 1/4

= 1/2

LB

Lý Bá Đức Thịnh

19 tháng 3 2023

5/9xx6/15=30/135=2/9 4/7:24/5=4/7xx5/24=5/42 6/11:4=6/11xx1/4=3/22 12xx19/18=12/1xx19/18=38/3 15 : 25/4=15/1xx4/25=12/5 1212/1515:2727/2525=1212/1515xx2525/2727=20/27 14/27 : 7/18 x 6/5+3/10=14/27xx18/7xx6/5+3/10=4/3xx6/5+3/10=8/5+3/10=16/10+3/10=19/10

Tính nhanh các biểu thức sau : a) (45 – 5 x 9) x 1 x 2 x 3 x 4 x 5 x 6 x 7 b) (1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10) x (72 – 8 x 8 – 8)c) (36 – 4 x 9) : (3 x 5 x 7 x 9 x 11)d) (27 – 3 x 9) : 9 x 1 x 3 x 5 x...

PT

Pham Trong Bach

10 tháng 3 2017

Đọc tiếp

3

CM

Cao Minh Tâm

10 tháng 3 2017

Ta có:

a) ( 45 – 5 x 9 ) x 1 x 2 x 3 x 4 x 5 x 6 x 7

= (45 – 45) x 1 x 2 x 3 x 4 x 5 x 6 x 7

= 0 x 1 x 2 x 3 x 4 x 5 x 6 x 7

= 0

b) (1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10) x (72 – 8 x 8 – 8)

= (1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10) x (72 – 64 – 8)

= (1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10) x 0

= 0

c) (36 – 4 x 9) : (3 x 5 x 7 x 9 x 11)

= (36 – 36) : (3 x 5 x 7 x 9 x 11)

= 0 : (3 x 5 x 7 x 9 x 11)

= 0

d) (27 – 3 x 9) : 9 x 1 x 3 x 5 x 7

= (27 – 27) : 9 x 1 x 3 x 5 x 7

= 0 : 9 x 1 x 3 x 5 x 7

=0

NT

Nguyễn Thanh Hương

22 tháng 3 2022

a) ( 45 – 5 x 9 ) x 1 x 2 x 3 x 4 x 5 x 6 x 7

= 0 x 1 x 2 x 3 x 4 x 5 x 6 x 7

b) (1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10) x (72 – 8 x 8 – 8)

= (1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 + 9 + 10) x 0

c) (36 – 4 x 9) : (3 x 5 x 7 x 9 x 11)

= 0 : (3 x 5 x 7 x 9 x 11)

d) (27 – 3 x 9) : 9 x 1 x 3 x 5 x 7

= 0 : 9 x 1 x 3 x 5 x 7 Nếu đúng thì k cho mình nhé bạn!

TN

Trần Nguyễn Ý Nhi

13 tháng 4 2017

1) Tính

a) 9/12 - 5/12 ; 9/12 - 1/3 ; 7 - 3/2 ; 9/4 - 2

b) 2/7 + 5/7 ; 1/3 + 5/12 ; 2 + 2/5 ; 6/9 + 3

c) 2/3 x 4/7 ; 3/11 x 2 ; 4 x 2/7

d) 8/21 : 4/7 ; 8/7 : 4 ; 5 : 2/3

AI LÀM NHANH VÀ ĐÚNG NHẤT THÌ MÌNH TICK CHO!!!!

5

V

vutanloc

13 tháng 4 2017

a] 4/12 ; 5/12 ; 11/2 ; 1/4

b] 1 ; 9/12; 12/5 ; 11/3

c] 8/21; 6/11;8/7

d] 2/3 ;2/7 15/2

TN

Trần Nguyễn Việt Hưng

13 tháng 4 2017

a]1/3 5/12 11/2 1/4

b]1 3/4 12/5 33/9

c]8/21 6/11 8/7

d]2/3 2/7 15/2

PT

Pham Trong Bach

25 tháng 8 2018

Tính:

8 + 1 = 7 + 2 = 6 + 3 = 5 + 4 =

1 + 8 = 2 + 7 = 3 + 6 = 4 + 5=

9 - 8 = 9 - 7 = 9 - 6 = 9 - 5 =

9 - 1 = 9 - 2 = 9 - 3 = 9 - 4 =

#Toán lớp 1

9

CM

Cao Minh Tâm

25 tháng 8 2018

8 + 1 = 9 7 + 2 = 9 6 + 3 = 9 5 + 4 = 9

1 + 8 = 9 2 + 7 = 9 3 + 6 = 9 4 + 5= 9

9 - 8 = 1 9 - 7 = 2 9 - 6 = 3 9 - 5 = 4

9 - 1 = 8 9 - 2 = 7 9 - 3 = 6 9 - 4 = 5

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R

roseandlisa

16 tháng 4 2021

Trả lời: 8 + 1 = 9 7 + 2 = 9 6 + 3 = 9 5 + 4 = 9 1 + 8 = 9 2 + 7 = 9 3 + 6 = 9 4 + 5=9 9 - 8 = 1 9 - 7 = 2 9 - 6 = 3 9 - 5 = 4 9 - 1 = 8 9 - 2 = 7 9 - 3 = 6 9 - 4 = 5

DN

Đỗ Nguyễn Vân Anh

27 tháng 11 2021

8/9 + 3/18 ; 5/7 - 4/11 ; 7/9 x 3/4 ; 12/7 : 1/4

3/4 + 4/5 ; 5/7 - 3/5 ; 8/3 x 21/4 ; 7/2 : 9/4

1

S

Sunny

27 tháng 11 2021

\(\dfrac{8}{9}+\dfrac{3}{18}=\dfrac{16}{18}+\dfrac{3}{18}=\dfrac{19}{18}\) \(\dfrac{5}{7}-\dfrac{4}{11}=\dfrac{55}{77}-\dfrac{28}{77}=\dfrac{3}{11}\)

\(\dfrac{3}{4}+\dfrac{4}{5}=\dfrac{15}{20}+\dfrac{16}{20}=\dfrac{21}{20}\) \(\dfrac{5}{7}-\dfrac{3}{5}=\dfrac{25}{35}-\dfrac{21}{35}=\dfrac{4}{35}\)

\(\dfrac{7}{9}X\dfrac{3}{4}=\dfrac{7}{9}X\dfrac{3}{4}=\dfrac{7}{12}\) \(\dfrac{8}{3}X\dfrac{21}{4}=\dfrac{8}{3}X\dfrac{21}{4}=14\)

\(\dfrac{12}{7}:\dfrac{1}{4}=\dfrac{12}{7}X\dfrac{4}{1}=\dfrac{48}{7}\) \(\dfrac{7}{2}:\dfrac{9}{4}=\dfrac{7}{2}X\dfrac{4}{9}=\dfrac{14}{9}\)

H

Haei

18 tháng 4 2023

Thực hiện phép tính:

1,-4/7 + 2/3x -9/14

2,17/13 - ( 4/13 - 11 )

3, 8 2/7 - ( 3 4/9 + 4 2/7 )

5, ( 2/3 - 1 1/2): 4/3 + 1/2

6, -5/13 + 2/5 + -8/13 + 3/5 - 3/7

7, 6/5 x 3/7 + 6/5 : 7/10 + 6/5

#Toán lớp 6

2

乇尺尺のﾚ

18 tháng 4 2023

\(1,-\dfrac{4}{7}+\dfrac{2}{3}\times\dfrac{-9}{14}\)

\(=\dfrac{-4}{7}+\dfrac{-18}{42}\)

\(=\dfrac{-4\times6}{7\times6}+\dfrac{-18}{42}\)

\(=\dfrac{-20}{42}+\dfrac{-18}{42}\)

\(=-\dfrac{38}{42}\)

\(=-\dfrac{19}{21}\)

\(2,\dfrac{17}{13}-\left(\dfrac{4}{13}-11\right)\)

\(=\dfrac{17}{13}-\dfrac{4}{13}+11\)

\(=\dfrac{13}{13}+11\)

\(=1+11\)

\(=12\)

\(3,8\dfrac{2}{7}-\left(3\dfrac{4}{9}+4\dfrac{2}{7}\right)\)

\(=\dfrac{58}{7}-\left(\dfrac{31}{9}+\dfrac{30}{7}\right)\)

\(=\dfrac{58}{7}-\dfrac{31}{9}-\dfrac{30}{7}\)

\(=\dfrac{58}{7}-\dfrac{30}{7}-\dfrac{31}{9}\)

\(=\dfrac{28}{7}-\dfrac{31}{9}\)

\(=\dfrac{28\times9}{7\times9}-\dfrac{31\times7}{9\times7}\)

\(=\dfrac{252}{63}-\dfrac{217}{63}\)

\(=\dfrac{35}{63}\)

\(=\dfrac{5}{9}\)

\(5,\left(\dfrac{2}{3}-1\dfrac{1}{2}\right):\dfrac{4}{3}+\dfrac{1}{2}\)

\(=\left(\dfrac{2}{3}-\dfrac{3}{2}\right):\dfrac{4}{3}+\dfrac{1}{2}\)

\(=\left(\dfrac{2\times2}{3\times2}-\dfrac{3\times3}{2\times3}\right):\dfrac{4}{3}+\dfrac{1}{2}\)

\(=\left(\dfrac{4}{6}-\dfrac{9}{6}\right):\dfrac{4}{3}+\dfrac{1}{2}\)

\(=\dfrac{-5}{6}:\dfrac{4}{3}+\dfrac{1}{2}\)

\(=\dfrac{-5}{6}\times\dfrac{3}{4}+\dfrac{1}{2}\)

\(=\dfrac{-15}{24}+\dfrac{1}{2}\)

\(=\dfrac{-15}{24}+\dfrac{1\times12}{2\times12}\)

\(=\dfrac{-15}{24}+\dfrac{12}{24}\)

\(=\dfrac{-3}{24}\)

\(=-\dfrac{1}{8}\)

\(6,\dfrac{-5}{13}+\dfrac{2}{5}+\dfrac{-8}{13}+\dfrac{3}{5}-\dfrac{3}{7}\)

\(=\left(\dfrac{-5}{13}+\dfrac{-8}{13}\right)+\left(\dfrac{2}{5}+\dfrac{3}{5}\right)-\dfrac{3}{7}\)

\(=\dfrac{-13}{13}+\dfrac{5}{5}-\dfrac{3}{7}\)

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

\(=-\dfrac{3}{7}\)

\(7,\dfrac{6}{5}\times\dfrac{3}{7}+\dfrac{6}{5}:\dfrac{7}{10}+\dfrac{6}{5}\)

\(=\dfrac{6}{5}\times\dfrac{3}{7}+\dfrac{6}{5}\times\dfrac{10}{7}+\dfrac{6}{5}\)

\(=\dfrac{6}{5}\times\left(\dfrac{3}{7}+\dfrac{10}{7}+1\right)\)

\(=\dfrac{6}{5}\times\left(\dfrac{3}{7}+\dfrac{10}{7}+\dfrac{1\times7}{1\times7}\right)\)

\(=\dfrac{6}{5}\times\left(\dfrac{3}{7}+\dfrac{10}{7}+\dfrac{7}{7}\right)\)

\(=\dfrac{6}{5}\times\dfrac{20}{7}\)

\(=\dfrac{120}{35}\)

\(=\dfrac{24}{7}\)

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NL

Nguyễn Lê Phước Thịnh

18 tháng 4 2023

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Đúng(1)

HY

Han Yujin

24 tháng 1

Tính hợp lý:

a) ( -5/6 + 2/5) : 3/8 + ( 4/5 - 11/30) : 3/8

b) (-3/4 + 2/5) : 3/7 + ( 3/5 + -1/4) : 3/7

c)-13/18 . 5/8 + -5/18 . 2/9 + -13/18 . 3/8 + -5/18 . 7/9

d) -11/19 . 4/9 + -8/19 . 3/7 + -11/19 . 5/9 + -9/19 . 4/7

#Toán lớp 6

2

NL

Nguyễn Lê Phước Thịnh

24 tháng 1

a: \(\left(-\dfrac{5}{6}+\dfrac{2}{5}\right):\dfrac{3}{8}+\left(\dfrac{4}{5}-\dfrac{11}{30}\right):\dfrac{3}{8}\)

\(=\left(-\dfrac{5}{6}+\dfrac{2}{5}\right)\cdot\dfrac{8}{3}+\left(\dfrac{4}{5}-\dfrac{11}{30}\right)\cdot\dfrac{8}{3}\)

\(=\dfrac{8}{3}\left(-\dfrac{5}{6}+\dfrac{2}{5}+\dfrac{4}{5}-\dfrac{11}{30}\right)\)

\(=\dfrac{8}{3}\cdot\dfrac{-25+36-11}{30}\)

=0

b: \(\left(-\dfrac{3}{4}+\dfrac{2}{5}\right):\dfrac{3}{7}+\left(\dfrac{3}{5}+\dfrac{-1}{4}\right):\dfrac{3}{7}\)

\(=\left(-\dfrac{3}{4}+\dfrac{2}{5}\right)\cdot\dfrac{7}{3}+\left(\dfrac{3}{5}-\dfrac{1}{4}\right)\cdot\dfrac{7}{3}\)

\(=\dfrac{7}{3}\left(-\dfrac{3}{4}+\dfrac{2}{5}+\dfrac{3}{5}-\dfrac{1}{4}\right)\)

\(=\dfrac{7}{3}\cdot0=0\)

c: \(\dfrac{-13}{18}\cdot\dfrac{5}{8}+\dfrac{-5}{18}\cdot\dfrac{2}{9}+\dfrac{-13}{18}\cdot\dfrac{3}{8}+\dfrac{-5}{18}\cdot\dfrac{7}{9}\)

\(=\left(-\dfrac{13}{18}\cdot\dfrac{5}{8}+\dfrac{-13}{18}\cdot\dfrac{3}{8}\right)+\left(-\dfrac{5}{18}\cdot\dfrac{2}{9}+\dfrac{-5}{18}\cdot\dfrac{7}{9}\right)\)

\(=-\dfrac{13}{18}\left(\dfrac{5}{8}+\dfrac{3}{8}\right)+\dfrac{-5}{18}\left(\dfrac{2}{9}+\dfrac{7}{9}\right)\)

\(=-\dfrac{13}{18}-\dfrac{5}{18}=-\dfrac{18}{18}=-1\)

d: Sửa đề: \(\dfrac{-11}{19}\cdot\dfrac{4}{9}+\dfrac{-8}{19}\cdot\dfrac{3}{7}+\dfrac{-11}{19}\cdot\dfrac{5}{9}+\dfrac{-8}{19}\cdot\dfrac{4}{7}\)

\(=\left(-\dfrac{11}{19}\cdot\dfrac{4}{9}+\dfrac{-11}{19}\cdot\dfrac{5}{9}\right)+\left(\dfrac{-8}{19}\cdot\dfrac{3}{7}+\dfrac{-8}{19}\cdot\dfrac{4}{7}\right)\)

\(=-\dfrac{11}{19}\left(\dfrac{4}{9}+\dfrac{5}{9}\right)+\dfrac{-8}{19}\left(\dfrac{3}{7}+\dfrac{4}{7}\right)\)

\(=-\dfrac{11}{19}-\dfrac{8}{19}=-\dfrac{19}{19}=-1\)

MP

Minh Phương

24 tháng 1

\(a.\left(-\dfrac{5}{6}+\dfrac{2}{5}\right):\dfrac{3}{8}+\left(\dfrac{4}{5}-\dfrac{11}{30}\right):\dfrac{3}{8}\)

\(=\left(-\dfrac{13}{30}\right):\dfrac{3}{8}+\dfrac{13}{30}:\dfrac{3}{8}\)

\(=\left[\left(-\dfrac{13}{30}+\dfrac{13}{30}\right)\right]:\dfrac{3}{8}\)

\(=0:\dfrac{3}{8}=0\)

\(b.\left(-\dfrac{3}{4}+\dfrac{2}{5}\right):\dfrac{3}{7}+\left(\dfrac{3}{5}+-\dfrac{1}{4}\right):\dfrac{3}{7}\)

\(=\left(-\dfrac{7}{20}\right):\dfrac{3}{7}+\dfrac{7}{20}:\dfrac{3}{7}\)

\(=\left[\left(-\dfrac{7}{20}+\dfrac{7}{20}\right)\right]:\dfrac{3}{7}=0:\dfrac{3}{7}=0\)

\(c.-\dfrac{13}{18}.\dfrac{5}{8}+-\dfrac{5}{18}.\dfrac{2}{9}+-\dfrac{13}{18}.\dfrac{3}{8}+-\dfrac{5}{18}.\dfrac{7}{9}\)

\(=\left(\dfrac{5}{8}+\dfrac{3}{8}\right).-\dfrac{13}{18}+\left(\dfrac{2}{9}+\dfrac{7}{9}\right).-\dfrac{5}{18}\)

\(=1.-\dfrac{13}{18}+1.-\dfrac{5}{18}=-\dfrac{13}{18}+-\dfrac{5}{18}=-1\)

\(d.-\dfrac{11}{19}.\dfrac{4}{9}+\dfrac{-8}{19}.\dfrac{3}{7}+-\dfrac{11}{19}.\dfrac{5}{9}+-\dfrac{9}{19}.\dfrac{4}{7}\)

\(=\left(\dfrac{4}{9}+\dfrac{5}{9}\right).-\dfrac{11}{19}+-\dfrac{24}{133}+-\dfrac{36}{133}\)

\(=-\dfrac{11}{19}+-\dfrac{60}{133}=-\dfrac{137}{133}\)