54.(53-81)+53.(81-54)

=(54-54)+(53-53).(21-81)

=0+0.0

=0

Tick mk du 100 nha.

\(54.\left(53-81\right)+53.\left(81-54\right)=53.54-54.81+53.81-53.54=53.81-54.81=81.\left(53-54=-81\right)\)

54.(53-81)+53.(81-54)

=54.53-54.81+53.81-53.54

=53.81-54.81

=-81

Tick mk vài cái lên 280 nha !!!

mk lấy xấp xỉ nhé

\(1,\left(54\right)\approx1,55\)

\(0,\left(81\right)\approx0,82\)

\(1,\left(54\right)-0\left(81\right)\approx1,55-0,82\approx0,73\)

hk tốt

\(1,\left(54\right)\approx2\)

\(0,\left(81\right)\approx1\)

\(1,\left(54\right)-0,\left(81\right)\approx2-1\approx1\)

hk tốt

\(1,\left(54\right)-0,\left(81\right)\)

\(=\left(1+54.\frac{1}{99}\right)-\left(81.\frac{1}{99}\right)\)

\(=\frac{17}{11}-\frac{9}{11}\)

\(=\frac{8}{11}\)

\(\frac{54\times107-53}{53\times107+54}=\frac{53\times107+107-53}{53\times107+54}=\frac{53\times107+54}{53\times107+54}=1\)

\(\frac{135\times269-134}{134\times269+135}=\frac{134\times269+269-134}{134\times269+135}=\frac{134\times269+135}{134\times269+135}=1\)

K⁰ đ

a) Trong các số đã cho:

b) – Các số đã cho theo thứ tự từ bé đến lớn: 46 530; 53 460; 53 640; 54 360.        

    – Các số đã cho theo thứ tự từ lớn đến bé: 54 360; 53 640; 53 460; 46 530.

\(43\left(53-81\right)+53\left(81-43\right)\)

\(=43.53-81+53.81-43\)

\(=81\left(53-43\right)\)

\(=81.10\)

\(=810\)

\(43\left(53-81\right)+53\left(81-43\right)\)

\(=43.53-43.81+53.81-53.43\)

\(=\left(43.53-53.43\right)+81\left(-43+53\right)\)

\(=0+81.10\)

\(=810\)

\(43\left(53-81\right)+53\left(81-43\right)\)

\(=43.53-81+53.81-43\)

\(=81\left(53-43\right)\)

\(=81.10\)

\(=810\)

Vài giây trước

?????

5 phút trước

Ta có:

57 : 53 = 54

57 : 54 = 53

57:53=1075471698

57:54=1055555556