Đáp án B

\(x-4\times25\%+10=200\)

\(=x-1+10=200\)

\(x-1=200-10\)

\(x-1=190\)

\(x=190+1\)

\(x=191\)

`a)25xx532xx4`

`=(25xx4)xx432`

`=432xx100=43200`

`b)456xx200-456xx100`

`=456xx(200-100)`

`=456xx100=45600`

\(a,25\times432\times4=25\times4\times432=100\times432=4320\\ b,456\times200-456\times100=456\times\left(200-100\right)=456\times100=45600\)

`25 xx 432 xx 4 = (25xx4 ) xx 432 = 100 xx 432 = 43200`

`456 xx200 - 456 xx 100 = 456 xx ( 200 - 100 ) = 456 xx 100 = 45600`

\(155-\frac{25}{2}\times4\times\frac{1}{10}+x\div\frac{3}{4}=200\)

\(\rightarrow155-5+x\div\frac{3}{4}=200\)

\(\rightarrow150+x\div\frac{3}{4}=200\)

\(\rightarrow x\div\frac{3}{4}=200-150\)

\(\rightarrow x\div\frac{3}{4}=50\)

\(\rightarrow x=50\times\frac{3}{4}\)

\(\rightarrow x=\frac{75}{2}\)

Vậy \(x=\frac{75}{2}\)

\(200:25-\left(12-x\right)=4\\ 8-\left(12-x\right)=4\\ 12-x=8-4\\ 12-x=4\\ x=12-4\\ x=8\\ ---\\ \left(x-10\right).5=100-20.4\\ \left(x-10\right).5=100-80=20\\ x-10=\dfrac{20}{5}=4\\ x=4+10=14\)

a)\(200:25-\left(12-x\right)=4\)

\(\Rightarrow8-\left(12-x\right)=4\)

\(\Rightarrow12-x=8-4\)

\(\Rightarrow12-x=4\)

\(\Rightarrow x=12-4\)

\(\Rightarrow x=8\)

b) \(\left(x-10\right)\cdot5=100-20\cdot4\)

\(\Rightarrow\left(x-10\right)\cdot5=100-80\)

\(\Rightarrow\left(x-10\right)\cdot5=20\)

\(\Rightarrow x-10=4\)

\(\Rightarrow x=10+4\)

\(\Rightarrow x=14\)

Đề bài : \(\dfrac{97}{20}\times\left(\dfrac{25}{8}-\dfrac{221}{200}\right)< x< \dfrac{91}{10}\times\left(\dfrac{137}{20}+\dfrac{11}{4}\right)\)

\(\dfrac{97}{20}\times\left(\dfrac{25}{8}-\dfrac{221}{200}\right)=\dfrac{97}{20}\times\dfrac{101}{50}=\dfrac{9797}{1000}\)

\(\dfrac{91}{10}\times\left(\dfrac{137}{20}+\dfrac{11}{4}\right)=\dfrac{91}{10}\times\dfrac{48}{5}=\dfrac{2184}{25}=\dfrac{2184\times40}{25\times40}=\dfrac{87360}{1000}\)

\(\Rightarrow\dfrac{9797}{1000}< x< \dfrac{87360}{1000}\)

Vậy \(x\in\left(\dfrac{9797}{1000};\dfrac{87360}{1000}\right)\)

a) (y + 5) x 2020 = 205 x 2020

(y + 5) x 2020 = 414100

y + 5 = 414100 : 2020 = 205

y = 205 - 5 = 200

a) y= 200

b) y-45600 = 1600 × 4 ×25

y-45600=160000

y= 114400

b) y - 45600 = (2019 - 419) x 4 x 25

y - 45600 = 1600 x 100

y - 45600 = 160000

y = 160000 + 45600 = 205 600

phần mik gửi vừa nãy là vt nhầm , nên mik gửi lại

1)[x-128+20] :192=0

    x-128+20        = 192

    x-128              = 192-20

    x-128              = 172

    x                     = 172+128

    x                     = 300

2) bạn nhớ check lại câu này giùm Nhi nha!

3) 460+85.4 = [ x+200] .4

    460+ 340 = 4x+ 800

     4x+800   = 800

      4x         = 800-800

      4x         = 0

        x         = 0:4

        x         = 0

bạn nhai ơi ban giải thích cho mình câu a đc ko vì sao lại bằng 192 chả nhẽ ko nhân hay làm gì với số ko ạ