( 3,5 - 70,84 : 23 + 4 - 3,375 . 49 ) : 0,78

= ( 3,5 - 3,08 + 4 - 165,375 ) : 0,78

= ( 0,42 + -161,375 ) : 0,78

= -160,955 : 0,78

= -220,7.

\(\frac{209}{156}\)

\(1)\dfrac{179}{50}-\left(\dfrac{59}{30}+\dfrac{3}{5}\right)\)

\(=\dfrac{179}{50}-\left(\dfrac{118}{60}+\dfrac{36}{60}\right)\)

\(=\dfrac{179}{50}-\dfrac{77}{30}\)

\(=\dfrac{537}{150}-\dfrac{385}{150}\)

\(=\dfrac{152}{150}=\dfrac{76}{75}=1\dfrac{1}{75}\)

Câu 1 : Ta có : 179/50 - ( 59/30 + 3/5 ) .

= 179/50 - ( 59/30 + 18/30 ) .

= 179/50 - 77/30 .

= 537/150 - 385/150.

= 76/75 .

Câu 2 : Ta có : ( 3,5 - 70,84 : 23 + 4 ) - 3,375 . 4/9 : 0,78 .

= ( 3,5 - 3,08 + 4 ) - 27/8 . 4/9 : 39/2 .

= 4,42 - 3/2 . 2/39 .

= 221/50 - 1/13 .

= 2873/650 - 50/650 .

= 2823/50 .

= 56,46 .

Câu 1:

\(\dfrac{179}{50}-\left(\dfrac{59}{30}+\dfrac{18}{30}\right)=\dfrac{179}{50}-\dfrac{77}{30}=\dfrac{537}{150}-\dfrac{385}{150}=\dfrac{152}{150}=\dfrac{76}{75}\)

Câu 2:

\(\left(3,5-70,84:23+4\right)-3,375.\dfrac{4}{9}:0,78=\left(3,5-3,08+4\right)-3,375.\dfrac{4}{9}:0,78=\left(0,42+4\right)-3,375.\dfrac{4}{9}:0,78=4,42-3,375.\dfrac{4}{9}:0,78=4,42-1,5:0,78=4,42-1,9230=2,497\)

1. Tính:

a) 23 + 24 - ( 65 x 2 - 4 ) x 4 + 66 + 44 - ( 54 : 9 x 9 : 9 + 45 ) : 1 + 1 - 1 x ( 23 + 23 - 23 x 2 +1 ) = 51

b) 4444444444444444444444444444444444444444444444444444444444444444444 : 1

= 4444444444444444444444444444444444444444444444444444444444444444444

c) 3⁰ = 0

d) 1/1 = 1

e)

a) - 530

b) 44444444444444444444444444444444444444444444444444444444444444444444

c) 0

d) 1

e) Em là em

-530

444444444444444444444444444444444444444444444444444444444444444

0

1

...

Giúp mình với hiccc

a,

23 x (7 - 4) = 23 x 3 = 69

23 x 7 - 23 x 4 = 161 - 92 = 69

Ta có: 23 x (7 - 4) = 23 x 7 - 23 x 4

b,

(8 - 3) x 9 = 5 x 9 = 45

8 x 9 - 3 x 9 = 72 - 27 = 45

Ta có: (8 - 3) x 9 = 8 x 9 - 3 x 9

TL: 

8/15 x 5/6 = 40/90 = 4/9 

41/20 x 3/4 = 123/80 

(11/23 + 9/23) + (18/23 + 2/23) = 20/23 + 20/23 = 40/43 

HT

\(\left(\frac{2}{3}\times\frac{4}{5}\right)\times\frac{5}{6}\) = \(\frac{2}{3}\times\frac{4}{5}\times\frac{5}{6}\)=\(\frac{2\times4\times5}{3\times5\times6}\)=\(\frac{2\times4\times5}{3\times5\times2\times3}\)=\(\frac{4}{9}\)

\(\frac{11}{23}+\frac{2}{23}+\frac{9}{23}+\frac{18}{23}\)=\(\frac{\left(11+9\right)+\left(18+2\right)}{23}\)=\(\frac{20+20}{23}\)=\(\frac{40}{23}\)

\(\frac{27}{12}+\frac{17}{6}-\frac{25}{36}-\frac{15}{6}\)=\(\left(\frac{27}{12}-\frac{25}{36}\right)+\left(\frac{17}{6}-\frac{15}{6}\right)\)=\(\frac{14}{9}+\frac{2}{6}\)=\(\frac{17}{9}\)

/HT\

Nhập các bạn toàn bắt tớ làm à ngu gò mà làm

=> x thuộc ƯC(70; 84)

Mà UWCLN(70; 84) = 14

=> x thuộc Ư(14)

=> x thuộc {1; 2; 7; 14}

Mà x > 8 => x = 14

Vậy...