a) C1:

218,3 - ( 5,6 + 111,82 )

= 218,3 - 117,42

= 100,88

C2:

218,3 - ( 5,6 + 111,82 )

= 218,3 - 111,82 - 5,6

= 106,48 - 5,6

= 100,88

b) C1:

72,83 - 30,6 - 16,4

= 42,23 - 16,4

= 25,83

C2:

72,83 - 30,6 - 16,4

= 72,83 - ( 30,6 + 16,4 )

= 72,83 - 47 

= 25,83

a) C1: 218.3 - ( 5.6 + 111.82 ) = 218.3 - 117.42 = 100.88

    C2: 218.3 - ( 5.6 + 111.82 ) = 218.3 - 5.6 - 111.82 = 212.7 - 111 .82 = 100.88

b) C1: 72.83 - 30.6 - 16.4 = 42.23 - 16.4 = 25.83

    C2: 72.83 - 30.6 - 16.4 = 72.83 - ( 30.6 + 16.4 ) = 72.83 - 47 = 25.83

Bạn tham khảo nhé!

a,

  97345 - 9205 x 3 + 7 x 9205

=  97345 - 9205 x (3 + 7)

=  97345 - 9205 x 10

=  97345 - 92050

= 5295

b,

4237-237x4+6x237

= 4237- 237x (4+6)

= 4237- 237x 10

= 4237- 2370

= 1867

1 giờ 90p + 10 giờ = 11 giờ 90 hay 12 giờ 30p

\(=\dfrac{5}{4}h+\dfrac{5}{4}h+10h\)

\(=\dfrac{25}{2}h\)

\(=\frac{\left(3\cdot3\cdot5\right)^{10}\cdot5^{20}}{\left(3\cdot5\cdot5\right)^{15}}\)

\(=\frac{3^{10}\cdot3^{10}\cdot5^{10}\cdot5^{20}}{3^{15}\cdot5^{15}\cdot5^{15}}\)

\(=\frac{3^{20}\cdot5^{30}}{3^{15}\cdot5^{30}}\)

\(=3^5=243\)

nhớ nha

\(a.x-c.y+a.y+b.x-c.x+b.y\)

\(=\)\(\left(ax+bx-cx\right)+\left(ay+by-cy\right)\)

\(=\)\(x.\left(a+b-c\right)+y.\left(a+b-c\right)\)

\(=\)\(\left(-3\right)x+\left(-3\right)y\)

\(=\)\(\left(-3\right).\left(x+y\right)\)

\(=\)\(\left(-3\right).15\)

\(=\)\(-45\)

Chúc bạn học tốt 

Bạn lấy bài này ở đâu thế ?

\(=\dfrac{8}{5}+\dfrac{18+2-14-6}{11}+\dfrac{8}{5}=\dfrac{16}{5}\)

A= (b+a)+(c+d)-(c+a)-(c+b)

A= b+a+c+d-c-a-c-b

A=(b-b) +(a-a)+(c-c-c)+d

A=0+0-c+d

A=-c+d

B=(a-b)-(d+a)-(c-d)+(c+d)
B=a-b-d-a-c+d+c+d
B=(a-a)+(b-b)+(c-c)+(d-d)
B=0+0+0+0
B=0
B