123×45+123×55

=123×(45+55)

=123×100

=12300

56×4+56×3+56×2+56

=56×4+56×3+56×2+56×1

=56×(4+3+2+1)

=56×10

=560

[ 123×154-65×123]:89

=[123×(154-65)]:89

= 123×89:89

=123×(89:89)

=123×1

=123

123 x 45 + 123 x 55

= 123 x ( 45 + 55 )

= 123 x 100

= 12300

56 x 4 + 56 x 3 + 56 x 2 + 56

= 56 x ( 4 + 3 + 2 + 1 ) 

= 56 x 10

= 560

[ 123 x 154 - 65 x 123 ] : 89

= [ 123 x ( 154 - 65 ) ] : 89

= [ 123 x 89 ] : 89

= 123

Học tốt #

123 x 45 + 123 x 55

= 123 x ( 45 + 55 )

= 123 x 100

= 12300

56 x 4 + 56 x 3 + 56 x 2 + 56

= 56 x ( 4 + 3 + 2 + 1 )

= 56 x 10

= 560

[123 x 154 - 65 x 123] : 89

= [ 123 x ( 154 - 65 ) ] : 89

= [ 123 x 89 ] : 89

= 123 x 89 : 89

= 123

= 339443775

= 176432256

k mik với

Câu hỏi :

23 x 45 x 67 x 89 x 55 = ?

34 x 78 x 99 x 12 x 56  = ?

Trả lời :

23 x 45 x 67 x 89 x 55 = 339443775

34 x 78 x 99 x 12 x 56  = 176432256

Chúc bạn học tốt !

23 x 45 x 67 x 89 x 55 = 339443775

34 x 78 x 99 x 12 x 56  = 176432256

x=-538

>

>

2 \(\times\) 3 \(\times\) 8 .... 45 - 5 \(\times\) 3

2 \(\times\) 3 \(\times\) 8 = 6 \(\times\) 8 = 48

\(45-5\times3\) = 45 - 15 = 30

Vì 48 > 40 nên 

2 \(\times\) 3 \(\times\) 8 > 45 - 5 \(\times\) 3

b, 46 + 56 .... 56 - 5 \(\times\) 3

   46 + 56 = 102

   56 - 5 \(\times\) 3 = 56 - 15 = 41

Vì 102 > 41  nên 

46 + 56  > 56 - 5 \(\times\) 6

>

>

`@` `\text {Ans}`

`\downarrow`

`a)`

`-(-18 + 45) - (18 + 55)`

`= 18 - 45 - 18 - 55`

`= (18 - 18) - (45 + 55)`

`= -100`

`b)`

`24. (5 - 178) + 178 . (10 + 24)`

`= 24.5 - 24.178 + 178. 10 + 178. 24`

`= 24.5 + 178.(-24 + 10 + 24)`

`= 24.5 + 178.10`

`=120 + 1780`

`=``1900`

`c)`

`29.(-101)`

`= -2929`

`d)`

\((- 56 + 130) – (43 – 56) – (- 20 – 43)\)

`= -56 + 130 - 43 + 56 + 20 + 43`

`= (56 - 56) + (130 + 20) + (-43+43)`

`= 150`

ảo ảo ảo

\(\dfrac{\text{88.10.23+45+56+55}}{2}\) =\(\dfrac{20240+45+56+55}{2}\) =\(\dfrac{20396}{2}\) =10198

20240+45+56+55220240+45+56+552 =

=10198

\(\left(\dfrac{x+1}{55}+\dfrac{x+2}{56}+\dfrac{x+3}{57}+\dfrac{x+4}{58}\right)-4=0\)

<=>\(\dfrac{x+1}{55}+\dfrac{x+2}{56}+\dfrac{x+3}{57}+\dfrac{x+4}{58}=4\)

<=>\(\dfrac{x+1}{55}-1+\dfrac{x+2}{56}-1+\dfrac{x+3}{57}+\dfrac{x+4}{58}-1=4-4\)

<=>\(\dfrac{x+1}{55}-\dfrac{55}{55}+\dfrac{x+2}{56}-\dfrac{56}{56}+\dfrac{x+3}{57}-\dfrac{57}{57}+\dfrac{x+4}{58}-\dfrac{58}{58}=0\)

<=>\(\dfrac{x-54}{55}+\dfrac{x-54}{56}+\dfrac{x-54}{57}+\dfrac{x-54}{58}=0\)

<=>\(\left(x-54\right)\left(\dfrac{1}{55}+\dfrac{1}{56}+\dfrac{1}{57}+\dfrac{1}{58}\right)=0\)

<=>x-54=0

<=>x=54

vậy phương trình có tập nghiệm là S={54}

=>\(\left(\dfrac{x+1}{55}-1\right)+\left(\dfrac{x+2}{56}-1\right)+\left(\dfrac{x+3}{57}-1\right)+\left(\dfrac{x+4}{58}-1\right)=0\)

=>x-54=0

=>x=54