=31+22+23-23+18

=31+40

=71

n: =345:(-345)=-1

n, (-15) x (-23) : (-345)

=   345  : (-345)

= -1

o, 36.55 - 185.11 + 121.5

 = 36.11.5 - 5.11.37 + 11.11.5

= 11.5.(36- 37 + 11)

= 11.5.10

= 550

a) \(\text{13 x 58 x 4 + 32 x 26 x 2 + 52 x 10 }\)

\(\text{=(13 x 4 ) x 58 + 32 x 13 x 2 x 2 + 13 x 4 x 10}\)

\(\text{= ( 13 x 4 ) x 58 + 32 x ( 13 x 2 x 2 ) + ( 13 x 4 ) x 10 }\)

\(\text{= 52 x 58 + 32 x 52 + 52 x 10}\)

\(\text{=52 x ( 58 + 32 + 10 )}\)

\(\text{=52 x 100 = 5200}\)

b) \(\text{14 x 35 x 5 + 10 x 25 x 7 + 20 x 70 x 2}\)

\(\text{= ( 14 x 5 ) x 35 + (10 x 7 ) x 25 + 20 x 70 x 2 }\)

\(\text{= 70 x 35 + 70 x 25 + 20 x 2 x 70 }\)

\(\text{= 70 x ( 35 + 25 + 40 )}\)

\(\text{= 70 x 100 = 7000 }\)

e) \(\text{5.3.37.4+5.24.21+21.5.12}\)

\(\text{= 5.(3.37.4+24.21+21.12)}\)

\(\text{= 5.1200}\)

\(=6000\)

a) \(13.58.4+32.26.2+52.10\)

\(=52.58+32.52+52.10\)

\(=52.\left(58+32+10\right)\)

\(=52.100=5200\)

b) \(14.35.5+10.25.7+20.70\)

\(=7.5.35.2+10.7.25+20.70\)

\(=35.70+70.25+20.70\)

\(=70\left(35+25+20\right)\)

\(=70.80=5600\)

c) \(...=15\left(27+18+6+23+12\right)\)

\(=15\left(27+23+18+12+6\right)\)

\(=15\left(50+30+6\right)=15.86=1290\)

d) \(...=53\left(51+4+49+96+1\right)\)

\(=53\left(51+49+4+96+1\right)\)

\(=53\left(100+100+1\right)=53.201=10653\)

e) \(15.37.4+120.21+21.5.12\)

\(=15.4.37+60.2.21+21.60\)

\(=60.37+60.42+21.60\)

\(=60.\left(37+42+21\right)=60.100=6000\)

a) 6,1 -  6,1 x 0,38 - 6,1 x 0,62 = 0

b)  21 11   ×   22 17   ×   68 63 =  8 3

Đề bài sai hả cậu

sao vậy 

sao lại 53:23, làm sao chia được

37(29-23)-29(37-23)

=37.29-37.23-37.29+29.23

=(37.29-37.29)-(37.23-29.23)

=-23(37-29)

=-23.8

=-184

Ta có :\(37.\left(29-23\right)-29.\left(37-23\right)=37.29-37.23-29.37+29.23\)

                                                                               \(=23.29-37.23\)

                                                                               \(=23.\left(29-37\right)\)

                                                                               \(=23.\left(-8\right)\)

                                                                               \(=-184\)

37. (29 − 23) − 29.(37 − 23)
=[ 37.29 − 37.23 ] − [ 29.37 − 29.23 ]
=(37.29)-(37.23)-(29.37)+(29.23)
=(29.23)-(37.23)
=23(29-37)
=23.(-8)
=-184

37 . (29 - 23) - 29. (37 - 23)

= 37 . 29 - 37 . 23 - 29 . 37 - 29 . 23

= 37 . (29 - 29) - 23 . (37 - 29)

= 37 . 0 - 23 . 8

= 0 - 184 

= 0 + (-184)

= -184

Hok Tốt

Có 37.(29-23)-29.(37-23)

=(37.29-37.23)-(29.37-29.23)

=37.29-37.23 - 29.37+29.23

=(37.29-29.37)-37.23+29.23

=0-184= -184

Ko biết mk lm đúng ko nếu sai thì mk xin lỗi nha

117 +68 + 23 = (117 +23) + 68 = 140 + 68 = 208.

117 + 68 + 23.

=(117+23)+68

=140+68

=208

117+68+23

=  117+ (68+23) 

=117+91

=208