$#Shả$

`A)=5/17xx(15/34+19/34)`

`=5/17xx1=5/17`

`B)=(13/12+7/12)+1/3`

`=5/3+1/3=2`

*Note: Tích của một số với 0 luôn bằng 0.

a) \(\left(1763+7634+23\cdot764\right)\cdot\left(346\cdot45-173\cdot90\right)\)

\(=\left(1763+7634+23\cdot764\right)\cdot\left(346\cdot45-173\cdot45\cdot2\right)\)

\(=\left(1763+7634+23\cdot764\right)\cdot\left(346\cdot45-346\cdot45\right)\)

\(=\left(1763+7634+23\cdot764\right)\cdot0\)

\(=0\)

b) \(N=10\cdot12\cdot14\cdot16\cdot\left(88\cdot17-44\cdot34\right)\)

\(N=10\cdot12\cdot14\cdot16\cdot\left(88\cdot17-44\cdot17\cdot2\right)\)

\(N=10\cdot12\cdot14\cdot16\cdot\left(88\cdot17-88\cdot17\right)\)

\(N=10\cdot12\cdot14\cdot16\cdot0\)

\(N=0\)

c) \(\left(80\cdot96+40\cdot1808\right):1000\)

\(=\left(80\cdot96+40\cdot904\cdot2\right):1000\)

\(=\left(80\cdot96+80\cdot904\right):1000\)

\(=\left[80\cdot\left(96+904\right)\right]:1000\)

\(=80\cdot1000:1000\)

\(=80\)

34 x 1 125 -25 x 34- 34 x 100

= 38 250 - 850 - 34 000

= 37 400 - 34 000

= 3 000

~HT~

Câu 2:Đáp số là 8/17 nhé

(5/9+4/9)x8/17

=>1x8/17=8/17

Câu 1: Tìm x:

a)  2/5× x =(thiếu đề)

 8/7: x =4/5 

x=8/7:4/5

x=10/7

Câu 2: Tính bằng cách thuận tiện nhất

5/9× 8/17 + 4/9 × 8/17

=(5/9+4/9)x8/17

=1x8/17=8/17

Câu 1

\(a,\dfrac{2}{5}\times x=4\\ x=4:\dfrac{2}{5}=10\\ b,7:x=\dfrac{4}{5}\\ x=\dfrac{4}{5}\times7=\dfrac{28}{5}\) 

Câu 2

\(=\left(\dfrac{5}{9}+\dfrac{4}{9}\right)\times\dfrac{8}{17}=1\times\dfrac{8}{17}=\dfrac{8}{17}\)

Câu 1: Tìm x:

a)  2/5× x = 4

x=4 : 2/5

x=10

 8/7: x =4/5 

x=8/7:4/5

x=10/7

Câu 2: Tính bằng cách thuận tiện nhất

5/9× 8/17 + 4/9 × 8/17

=(5/9+4/9)x8/17

=1x8/17=8/17

\(5/9× 8/17 + 4/9 × 8/17 =>(5/9+4/9)×8/17 =>1 ×8/17=8/17\)

Câu 2:

a: x-158=32

=>x=158+32

=>x=190

b: \(x\cdot24=264\)

=>\(x=\dfrac{264}{24}\)

=>x=11

c: \(6x+9=3^7:3^4\)

=>\(6x+9=3^3\)

=>6x+9=27

=>6x=18

=>x=18/6=3

Câu 1:

a: \(86\cdot19+14\cdot19\)

\(=19\left(86+14\right)\)

\(=19\cdot100=1900\)

b: \(4\cdot\left(-5\right)^2-104\cdot\left(-5\right)^2\)

\(=4\cdot25-104\cdot25\)

\(=25\left(4-104\right)=-100\cdot25=-2500\)

c: \(7\cdot\left(-2\right)\cdot8\left(-5\right)\)

\(=7\cdot2\cdot8\cdot5\)

\(=56\cdot10=560\)

d: \(59-\left[59+\left(-76\right)\right]\)

\(=59-59+76\)

=76

1.\(\dfrac{11}{8}\)

2.A)739\(\times\) (2+1+3+4)=7390

B)801\(\times\) (67+34-1)=80100

  3/4 x 7/12 + 3/4 x 1/6 + 3/4 x 1/4

=3/4 x (7/12 + 1/6 + 1/4)

=3/4 x (7/12 + 2/12 + 3/12)

=3/4 x 1

=3/4

Chúc học tốt~

3/4x7/12+3/4x1/6+3/4x1/4=3/4x(7/12+1/6+1/4)=3/4x1=3/4

cam on

a) 23,5 x 34 + 45 x 23,5 + 3 x 23,5 x 7

= 23,5 x (34 + 45 + 3 x 7)

= 23,5 x (34 + 45 + 21)

=23,5 x 100

= 235.

b) 126 x 56 + 252 x 0,5 x 35 + 42 x 3 x 9

= 42 x 3 x 56 + 126 x 35 + 42 x 3 x 9

= 42 x 168 + 42 x 3 x 35 + 42 x 3 x 9

= 42 x 168 + 42 x 105 + 42 x 27

= 42 x (168 + 105 + 27)

= 42 x 300

= 12600

tick mình nha!

a) 23,5 x 34 + 45 x 23,5 + 3 x 23,5 x 7

= 23,5 x (34 + 45 + 3 x 7)

= 23,5 x (34 + 45 + 21)

=23,5 x 100

= 235.

b) 126 x 56 + 252 x 0,5 x 35 + 42 x 3 x 9

= 42 x 3 x 56 + 126 x 35 + 42 x 3 x 9

= 42 x 168 + 42 x 3 x 35 + 42 x 3 x 9

= 42 x 168 + 42 x 105 + 42 x 27

= 42 x (168 + 105 + 27)

= 42 x 300

= 12600