a)(4,53 . 0,2 + 6,165.3) :2,5 = (0,906 +18,495) : 2,5 = 19,401 : 2,5 =7, 7604

(4,53.0,2+6,165.3):25=0,77604

Cam on ban nhieu nha

a; (-2,5.0,38.0,4) - {0,125.3,15.(-8)}

= (-2.5.0,4).0,38 - {-8.0,125.3,15}

= - 1.0,38 - {-1.3,15}

= -0,38 + 3,15

= 2,77

b; {(-20,83).0,2 + (-9,17).0,2 : {2,47.0,5 - (-3,53.0,5}

= {0,2.(-20,83 - 9,17)}: {0,5.(2,47 + 3,53)}

= {- 0,2.30}:{0,5.6}

= - 6:6 : 0,5

= -1 : 0,5

= - 2 

-4 . (-3 . 15) . 2,5 - 1,25 . (-4,1) . 8 + 0,2

= -4 . (-45) . 2,5 - (-5,125) . 8 + 0,2

= 180 . 2,5 - (-41) + 0,2

= 450 + 41 + 0,2

= 491,2

sai thì thôi nha!

a) \(x:0,1+x:0,2=5,1\)

\(\Leftrightarrow x:\left(0,1+0,2\right)=5,1\)

\(\Leftrightarrow x:0,3=5,1\)

\(\Leftrightarrow x=5,1.0,3\)

\(\Leftrightarrow x=1,53\)

b) \(5:x-2,6:x=2,5\)

\(\Leftrightarrow\left(5-2,6\right):x=2,5\)

\(\Leftrightarrow2,4:x=2,5\)

\(\Leftrightarrow x=2,4:2,5\)

\(\Leftrightarrow x=0,96\)

\(a)\) \(x:0,1+x:0,2=5,1\)

\(x:\left(0,1+0,2\right)=5,1\)

\(x:0,3=5,1\)

\(x=5,1.0,3\)

\(x=1,53\)

\(b)5:x-2,6:x=2,5\)

\(x:\left(5-2,6\right)=2,5\)

\(x:2,4=2,5\)

\(x=2,5.2,4\)

\(x=6\)

a) TH1: \(x< 2,5\) , ta có:

\(2,5-x=1,3\)

\(x=2,5-1,3=1,2\)

TH2: \(x\ge2,5\), ta có:

\(x-2,5=1,3\)

\(x=1,3+2,5=3,8\)

Vậy \(\orbr{\begin{cases}x=1,2\\x=3,8\end{cases}}\)

b) \(1,6-\left|x-0,2\right|=0\)

\(\Rightarrow\left|x-0,2\right|=1,6\)

TH1: \(x< 0,2\) ta có:

\(0,2-x=1,6\Rightarrow x=0,2-1,6=-1,4\)

TH2: \(x\ge0,2\) ta có:

\(x-0,2=1,6\Rightarrow x=1,6+0,2=1,8\)

Vậy \(\orbr{\begin{cases}x=-1,4\\x=1,8\end{cases}}\)

a)\(\left[\left(-50,17\right).0,2+\left(-9,83\right).0,2\right]:0,2\)

=\(\left[\left[\left(-50,17\right)+\left(-9,83\right)\right].0,2\right]:0.2\)

=\(\left[\left(-60\right).0,2\right]:0,2\)

=\(\left(-12\right):0,2\)

=\(-60\)

b)\(\left[\left(-30,17\right).0,2+\left(-9,83\right).0,2\right]-\left[4,48-\left(-2,52\right)\right]:0,4\)

=\(\left\{\left[\left(-30,17\right)+\left(-9,83\right)\right].0,2\right\}-\left(4,48+2,52\right):0,4\)

=\(\left[\left(-40\right).0,2\right]-7:0,4\)

=\(\left(-8\right)-17,5\)

=\(-25,5\)