K
Khách

Hãy nhập câu hỏi của bạn vào đây, nếu là tài khoản VIP, bạn sẽ được ưu tiên trả lời.

23 tháng 2 2019

a) \(\frac{5}{12}-\frac{3}{-16}+\frac{3}{4}\)

\(=\frac{5}{12}-\left(-\frac{3}{16}\right)+\frac{3}{4}\)

\(=\frac{5}{12}+\frac{3}{6}+\frac{3}{4}\)

\(=\frac{20+9+36}{48}\)

\(=\frac{65}{48}\)

Mấy câu kia lát làm :))

23 tháng 2 2019

b) \(\frac{17}{-34}+\frac{25}{75}+\frac{121}{132}\)

\(=-\frac{1}{2}+\frac{1}{3}+\frac{121}{123}\)

\(=-\frac{123}{246}+\frac{82}{246}+\frac{242}{246}\)

\(=\frac{-123+82+242}{246}\)

\(=\frac{201}{246}=\frac{67}{82}\)

`@` `\text {Ans}`

`\downarrow`

`a)`

\(\dfrac{3}{4}+\dfrac{2}{3}+\dfrac{3}{5}\)

`=`\(\dfrac{9}{12}+\dfrac{8}{12}+\dfrac{3}{5}\)

`=`\(\dfrac{17}{12}+\dfrac{3}{5}\)

`=`\(\dfrac{85}{60}+\dfrac{36}{60}\)

`=`\(\dfrac{121}{60}\)

`b)`

\(\dfrac{1}{2}\cdot\dfrac{9}{13}\div\dfrac{27}{26}\)

`=`\(\dfrac{1}{2}\cdot\dfrac{9}{13}\cdot\dfrac{26}{27}\)

`=`\(\dfrac{1}{2}\cdot\dfrac{2}{3}\)

`=`\(\dfrac{1}{3}\)

`c)`

\(\dfrac{2}{7}\cdot\dfrac{1}{9}+\dfrac{2}{7}\cdot\dfrac{2}{9}+\dfrac{1}{3}\cdot\dfrac{5}{7}\)

`=`\(\dfrac{2}{7}\cdot\left(\dfrac{1}{9}+\dfrac{2}{9}\right)+\dfrac{1}{3}\cdot\dfrac{5}{7}\)

`=`\(\dfrac{2}{7}\cdot\dfrac{1}{3}+\dfrac{1}{3}\cdot\dfrac{5}{7}\)

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

`=`\(\dfrac{1}{3}\cdot1=\dfrac{1}{3}\)

`d)`

\(11\div\dfrac{5}{2}+11\div\dfrac{7}{3}+11\div\dfrac{35}{6}\)

`=`\(11\cdot\dfrac{2}{5}+11\cdot\dfrac{3}{7}+11\cdot\dfrac{6}{35}\)

`=`\(11\cdot\left(\dfrac{2}{5}+\dfrac{3}{7}+\dfrac{6}{35}\right)\)

`=`\(11\cdot1=11\)

19 tháng 7 2023

a) 3/4 + 2/3 + 3/5 = 45/60 + 40/60 + 36/60 = 121/60

b) 1/2 x 9/13 : 27/26 = 9/26 x 26/27 = 1/3

c) 2/7 x 1/9 + 2/7 x 2/9 + 1/3 x 5/7 = 2/7 x (1/9 + 2/9) + 5/21 = 2/7 x 1/3 + 5/21 = 2/21 + 5/21 = 1/3

d) 11 : 5/2 + 11 : 7:3 + 11 : 35/6 = 11 x (2/5 + 3/7 + 6/35) = 11 x 1 = 11 

a: \(=\left(15-6-\dfrac{13}{18}\right):\dfrac{298}{27}-\dfrac{17}{8}:\dfrac{51}{40}\)

\(=\dfrac{149}{18}\cdot\dfrac{27}{298}-\dfrac{5}{3}=\dfrac{3}{2}-\dfrac{5}{3}=\dfrac{9-10}{6}=\dfrac{-1}{6}\)

b: \(=\dfrac{-16}{5}\cdot\dfrac{-15}{64}+\dfrac{-22}{15}:\dfrac{11}{2}\)

\(=\dfrac{3}{4}-\dfrac{4}{15}=\dfrac{29}{60}\)

c: \(=\dfrac{-7}{9}\left(\dfrac{4}{11}+\dfrac{7}{11}\right)+5+\dfrac{7}{9}=\dfrac{-7}{9}+\dfrac{7}{9}+5=5\)

d: \(=\dfrac{1}{2}\cdot\dfrac{4}{3}\cdot10\cdot\dfrac{1}{5}\cdot\dfrac{3}{4}=1\)

e: \(=\dfrac{4}{25}+\dfrac{11}{2}\cdot\dfrac{5}{2}+\dfrac{-23}{4}=\dfrac{204}{25}\)

a: \(\dfrac{18}{24}+\dfrac{35}{-21}-\dfrac{1}{2}\)

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

\(=\dfrac{9-20-6}{12}=\dfrac{-17}{12}\)

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

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

\(=\dfrac{-8+9-10}{12}=\dfrac{-9}{12}=\dfrac{-3}{4}\)

c: \(\left(\dfrac{3}{4}+\dfrac{-7}{2}\right)\cdot\left(\dfrac{10}{11}+\dfrac{2}{22}\right)\)

\(=\left(\dfrac{3}{4}-\dfrac{14}{4}\right)\cdot\left(\dfrac{10}{11}+\dfrac{1}{11}\right)\)

\(=-\dfrac{11}{4}\cdot1=-\dfrac{11}{4}\)

d: \(\left(\dfrac{7}{3}-\dfrac{-7}{2}\right):\left(-\dfrac{25}{6}\cdot\dfrac{1}{5}\right)\)

\(=\left(\dfrac{7}{3}+\dfrac{7}{2}\right):\dfrac{-5}{6}\)

\(=\dfrac{35}{6}\cdot\dfrac{6}{-5}=\dfrac{35}{-5}=-7\)

29 tháng 1

a) \(\dfrac{18}{24}+\dfrac{35}{-21}-\dfrac{1}{2}\)

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

\(=\dfrac{9}{12}-\dfrac{20}{12}-\dfrac{6}{12}\)

\(=\dfrac{-17}{12}\)

b) \(\dfrac{-2}{3}-\dfrac{3}{-4}+\dfrac{5}{-6}\)

\(=\dfrac{-8}{12}+\dfrac{9}{12}-\dfrac{10}{12}\)

\(=\dfrac{-9}{12}\)

\(=\dfrac{-3}{4}\)

c) \(\left(\dfrac{3}{4}+\dfrac{-7}{2}\right).\left(\dfrac{10}{11}+\dfrac{2}{22}\right)\)

\(=\dfrac{-11}{4}.1\)

\(=\dfrac{-11}{4}\)

d) \(\left(\dfrac{7}{3}-\dfrac{-7}{2}\right):\left(-\dfrac{25}{6}.\dfrac{1}{5}\right)\)

\(=\dfrac{35}{6}:\dfrac{-5}{6}\)

\(=-7\)

2 tháng 3 2022

\(\dfrac{1}{6}+\dfrac{-2}{5}=\dfrac{5}{30}+\dfrac{-12}{30}=\dfrac{-7}{30}\)

\(\dfrac{5}{12}-\dfrac{7}{8}=\dfrac{10}{24}-\dfrac{21}{24}=\dfrac{-11}{24}\)

\(\dfrac{-4}{25}:\dfrac{-32}{45}=\dfrac{-4}{25}.\dfrac{-45}{32}=\dfrac{-1}{5}.\dfrac{-9}{8}=\dfrac{4}{40}\)

\(\dfrac{-2}{9}.\dfrac{7}{11}+\dfrac{-2}{9}.\dfrac{10}{11}+\dfrac{-2}{9}.\dfrac{5}{11}=\dfrac{-2}{9}\left(\dfrac{7}{11}+\dfrac{10}{11}+\dfrac{5}{11}\right)=\dfrac{-2}{9}.\dfrac{22}{11}=\dfrac{-2}{9}.2=\dfrac{-4}{9}\)

2: 

a: =>x=1/2+1/6=3/6+1/6=4/6=2/3

b: =>x+3,5=7,8-6,3=1,5

=>x=1,5-3,5=-2

c: =>(35-x)/-105=1/5

=>35-x=-21

=>x=56

27 tháng 6 2023

1

c hình như tính bình thường thôi:v

d

= 1,75 : 5 + 2,5 . (16 – 4 . 4,1)

= 1,75 : 5 + 2,5 . (16 – 16,4)

= 1,75 : 5 + 2,5 . (−0,4)

= 0,35 − 1

= −0,65.

2

a

\(\Rightarrow x=\dfrac{1}{2}+\dfrac{1}{6}=\dfrac{3}{6}+\dfrac{1}{6}=\dfrac{4}{6}=\dfrac{2}{3}\)

b

\(\Rightarrow x+\dfrac{35}{10}=\dfrac{78}{10}-\dfrac{63}{5}:2\\ \Rightarrow x+\dfrac{35}{10}=\dfrac{78}{10}-\dfrac{63}{10}=\dfrac{15}{10}\\ \Rightarrow x=\dfrac{15}{10}-\dfrac{35}{10}=-2\)

c không rõ đề:v

a: \(=\dfrac{4\cdot2+4\cdot9}{55}+\dfrac{5}{6}=\dfrac{4}{5}+\dfrac{5}{6}=\dfrac{49}{30}\)

b: \(=\dfrac{3}{2}\cdot\dfrac{3}{5}-\left(\dfrac{3}{7}+\dfrac{3}{20}\right)\cdot\dfrac{10}{3}\)

\(=\dfrac{9}{10}-\dfrac{81}{140}\cdot\dfrac{10}{3}\)

\(=\dfrac{9}{10}-\dfrac{27}{14}=\dfrac{-36}{35}\)

c: \(=15+\dfrac{3}{13}-3-\dfrac{4}{7}-8-\dfrac{3}{13}\)

\(=4-\dfrac{4}{7}=\dfrac{24}{7}\)

d: \(=\dfrac{-7}{9}\left(\dfrac{4}{11}+\dfrac{7}{11}\right)+5+\dfrac{7}{9}=5\)

a: =35/17-18/17-9/5+4/5

=1-1=0

b: =-7/19(3/17+8/11-1)

=7/19*18/187=126/3553

c: =26/15-11/15-17/3-6/13

=1-6/13-17/3

=7/13-17/3=-200/39

20 tháng 7 2018

\(A=\frac{4}{3.7}+\frac{4}{7.11}+...+\frac{4}{107.111}\)

\(A=\frac{1}{3}-\frac{1}{7}+\frac{1}{7}-\frac{1}{11}+...+\frac{1}{107}-\frac{1}{111}\)

\(A=\frac{1}{3}-\frac{1}{111}\)

\(A=\frac{12}{37}\)

mà dài quá bạn ơi ban tách ra thành nhiều câu hỏi đi thế này trả lời lâu lắm