1. -11200

2. -378900

3. -11200

4. 1200

-11200

-378900

-11200

-69

\(213=\)\(2.10^2\)   \(+1.10+3.10^0\)

\(421=4.10^2+2.10+1.10^0\) 

\(1256=1.10^3+2.10^2+1.10^0\) 

\(2006=2.10^3+0.10^2+0.10+6.10^0\) 

abc = a . 10 ^2 + b .10 + c .10 ^ 0

abcde = a.10 ^ 4 + b.10^3 + c.10^ 2+ d .10 + e . 10 ^ 0

k cho mk nha

a) 213 = 2 . 10² + 1 . 10¹ + 3 . 10⁰

b) 1256 = 1 . 10³ + 2 . 10² + 5 . 10¹ + 6 . 10⁰

c) abc = a . 10² + b . 10¹ + c . 10⁰

e)abcde = a . 10⁴ + b . 10³ + c . 10² + d . 10¹ + e . 10⁰

x.25+38+75.x=3680

x.25+x.75+38=3680

x.25+x.75=3642

x.(25+75)=3642

x.100=3642

x=342:100

x=36,42

tk nhe

x.25+38+75.x=3680

100x+38=3680

100x     =3642

x          =36,42

ai tk minh thi minh tk lai 

455 + (-311) + 3789 + (-144 )

= 455 - 311 + 3789 - 144

= 144 + 3789 - 144

= (144 - 144) + 3789

= 0 + 3789

= 3789

A= -27,9999973

LAm chi tiet duoc khong ban

2179x1862

=>Tích là 40515258

3789:231

=>Thương là 16, dư là 93

9848:345

=>Thương là 28, dư là 188

a) \(A=455+\left(-311\right)+3789+\left(-144\right)\)

\(\Rightarrow A=455-311+3789-144\)

\(\Rightarrow A=144+3645=3789\)

Vậy A = 3789

b) \(B=815+\left[95+\left(-815\right)+\left(-45\right)\right]\)

\(\Rightarrow B=815+\left(95-860\right)\)

\(\Rightarrow B=815-770=45\)

Vậy B = 45