1000            

9-4+1+234-34+234-34+234-34+234-34+234-34-6

=1000

tick nha!

1000                              

Giải:

\(\left(\dfrac{1}{4}+\dfrac{11}{9}\right):\dfrac{34}{5}+\left(\dfrac{-2}{9}+\dfrac{29}{4}\right):\dfrac{34}{5}\)

\(=\left(\dfrac{1}{4}+\dfrac{11}{9}\right).\dfrac{5}{34}+\left(\dfrac{-2}{9}+\dfrac{29}{4}\right).\dfrac{5}{34}\)

\(=\left[\left(\dfrac{1}{4}+\dfrac{11}{9}\right)+\left(\dfrac{-2}{9}+\dfrac{29}{4}\right)\right].\dfrac{5}{34}\)

\(=\left[\dfrac{1}{4}+\dfrac{11}{9}-\dfrac{2}{9}+\dfrac{29}{4}\right].\dfrac{5}{34}\)

\(=\left[\dfrac{9}{9}+\dfrac{30}{4}\right].\dfrac{5}{34}\)

\(=\left[1+\dfrac{15}{2}\right].\dfrac{5}{34}\)

\(=\dfrac{17}{2}.\dfrac{5}{34}\)

\(=\dfrac{5}{4}\)

Vậy ...

40 phút nhé

10 phút

Mình nhầm 40 phút

200

Đáp án là D

34 - (25 + 34) = x - (25 - 9)

34 - 25 - 34 = x - 16

34 - 34 - 25 = x - 16

-25 = x - 16

-25 + 16 = x

-(25 - 16) = x

-9 = x

`15/34+7/21+9/34-1 15/17+2/3`

`=(15/34+9/34)+(7/21+2/3)-32/17`

`=12/17+1-32/17`

`=(12/17-32/17)+1`

`=-20/17+1`

`=-3/17`

\(\dfrac{15}{34}+\dfrac{7}{21}+\dfrac{9}{34}-1\dfrac{15}{17}+\dfrac{2}{3}\)
\(=\left(\dfrac{15}{34}+\dfrac{9}{34}-\dfrac{32}{17}\right)+\left(\dfrac{1}{3}+\dfrac{2}{3}\right)\)
\(=-\dfrac{25}{17}+1=-\dfrac{8}{17}\)

A

Bài 7. Tính nhanh giá trị biểu thức: 34 × 12 + 34 × 7 – 34 × 9:

C. 2400

D. 3210

B. 3400

A. 340

a

ap dung nhan chia truoc cong tru sau

Sửa đề:

\(A=\dfrac{15}{34}+\dfrac{7}{21}+\dfrac{9}{34}-1\dfrac{15}{17}+\dfrac{2}{3}\)

\(=\dfrac{15}{34}+\dfrac{7}{21}+\dfrac{9}{34}-\dfrac{32}{17}+\dfrac{2}{3}\)

\(=-\dfrac{3}{17}\)

Cái hạng tử thứ 4 là gì vậy ạ?