\(A=-5,13:\left(5\dfrac{5}{28}-1\dfrac{8}{9}.1,25+1\dfrac{16}{63}\right)\)

\(=-5,13:\left(5\dfrac{5}{28}-2\dfrac{13}{36}+1\dfrac{16}{63}\right)\)

\(=5,13:\left[\left(5-2+1\right)+\left(\dfrac{5}{28}-\dfrac{13}{36}+\dfrac{16}{63}\right)\right]\)

\(=5,13:\left(4+\dfrac{1}{14}\right)\)

\(=1,26\)

`A=-5,13:(5 5/28-1 8/9 .1,25+1 16/63)`

`A=-513/100:(145/28-17/9 .5/4+79/63)`

`A=-513/100:(145/28-85/36+79/63)`

`A=-513/100:(355/126+79/63)`

`A=-513/100:57/14`

`A=-63/50`

\(A=-5,13:\left(5\dfrac{5}{28}-1\dfrac{8}{9}.1,25+1\dfrac{16}{63}\right)\)

\(A=-5,13:\left[\left(5-2+1\right)+\left(\dfrac{5}{28}-\dfrac{18}{36}+\dfrac{16}{63}\right)\right]\)

\(A=-5,13:\left(4+\dfrac{1}{14}\right)\)

\(A=-5,13:\left(\dfrac{56}{14}+\dfrac{1}{14}\right)\)

\(A=-5,13:\dfrac{57}{14}\)

\(A=\dfrac{-513}{100}:\dfrac{57}{14}\)

\(A=\dfrac{-513}{100}\times\dfrac{14}{57}\)

\(A=\dfrac{-63}{50}\)

A= -5,13: (\(5\dfrac{5}{28}\)-\(1\dfrac{8}{9}\).1,25+\(1\dfrac{16}{63}\))

A=-5,13:(\(\dfrac{145}{28}\)-\(\dfrac{17}{9}\). 1,25+\(\dfrac{79}{63}\))

A= -5,13:(\(\dfrac{145}{28}\)-\(\dfrac{85}{36}\)+ \(\dfrac{79}{63}\))

A= -5,13:\(\dfrac{57}{14}\)

A= -\(\dfrac{63}{50}\)

\(A=-5,13:\left(5\dfrac{5}{28}-1\dfrac{8}{9}.1,25+1\dfrac{16}{63}\right)\)

\(A=-5,13:\left(5\dfrac{5}{28}-\dfrac{85}{36}+1\dfrac{16}{63}\right)\)

\(A=-5,13:\dfrac{57}{14}\)

\(A=\dfrac{-63}{50}\)

\(A=-5,13:\left(\dfrac{5\cdot28+5}{28}-\dfrac{1\cdot9+8}{9}\cdot1,25+\dfrac{1\cdot63+16}{63}\right)\)

\(A=-5,13:\left(\dfrac{145}{28}-\dfrac{85}{36}+\dfrac{79}{63}\right)\)

\(A=-5,13:\left(\dfrac{57}{14}\right)=-5,13\cdot\dfrac{14}{57}=-\dfrac{63}{50}\)

CHÚC BẠN HỌC TỐT !!!

\(A=-5,13:\left(5\dfrac{5}{28}-1\dfrac{8}{9}.1,25+1\dfrac{16}{63}\right)\)

\(=-5,13:\left(\dfrac{145}{28}-\dfrac{17}{9}.\dfrac{125}{100}+\dfrac{79}{63}\right)\)

\(=-5,13:\left(\dfrac{145}{28}-\dfrac{17}{9}.\dfrac{5}{4}+\dfrac{79}{63}\right)\)

\(=-5,13:\left(\dfrac{145}{28}-\dfrac{85}{36}+\dfrac{79}{63}\right)\)

\(=-5,13:\dfrac{57}{14}=-5,13:\dfrac{15}{57}\)

\(=\dfrac{-71,82}{57}=1,26\)

Vậy \(A=1,26\)

\(B=\left(3\dfrac{1}{3}.1,9+19,5:4\dfrac{1}{3}\right).\left(\dfrac{62}{75}-\dfrac{4}{25}\right)\)

\(=\left(\dfrac{10}{3}.1,9+19,5:\dfrac{13}{3}\right).\left(\dfrac{62-12}{75}\right)\)

\(=\left(\dfrac{19}{3}+\dfrac{58,5}{13}\right).\dfrac{50}{75}\)

\(=\left(\dfrac{19}{3}+4,5\right).\dfrac{2}{3}\)

\(=\dfrac{32,5}{3}.\dfrac{2}{3}=\dfrac{65}{9}=7\dfrac{2}{9}\)

Vậy \(B=7\dfrac{2}{9}\)

\(A=-5,13:\left(5\frac{5}{28}-1\frac{8}{9}.1,25+1\frac{16}{63}\right)\)

\(A=-5,13:\left(5\frac{5}{28}-\frac{85}{36}+1\frac{16}{63}\right)\)

\(A=-5,13:\frac{57}{14}=-\frac{63}{50}\)

\(B=\left(3\frac{1}{3}.1,9+19,5:4\frac{1}{3}\right).\left(\frac{62}{72}-\frac{4}{25}\right)\)

\(B=\left(\frac{19}{3}+\frac{9}{2}\right).\frac{631}{900}\)

\(B=\frac{65}{6}.\frac{631}{900}=\frac{8203}{1080}\)

dấu * là dấu nhân nha

cái này bn dùng máy tính cho nhanh

bạn lấy máy tính tính nhé

bn tính từng phần nhân chia trước cộng trừ sau!

bấm máy là xog

Bài 1:

a) Ta có:

\(3,2\cdot x+\left(-1,2\right)\cdot x+2,7=-4,9\)

\(\Rightarrow\left[3,2+\left(-1,2\right)\right]\cdot x=\left(-4,9\right)-2,7\)

\(\Rightarrow2x=-7,6\)

\(\Rightarrow x=\left(-7,6\right):2\)

\(\Rightarrow x=-3,8\)

Vậy \(x=-3,8\)

b) Ta có:

-5,6.x+2,9.x-3,86=-9,8

=>[(-5,6)+2,9].x=(-9,8)+3,86

=>(-2,7).x=-5,94

=>x=(-5,94):(-2,7)

=>x=2,3

Vậy x=2,2

Dễ mà. ấn máy tính cũng ra