=146+287+158+187+158+546

=692+474+316

=1482

= 146 + 287 + 158 + 187 + 158 + 546
= 100 + 46 + 200 + 87 + 100 + 58 + 100 +87 +100 +58 +500 + 46
=(100+200+100+100+100+500) + (46+46+87+87+ 58+58)
=1100 + 2 x (46 + 87 + 58)
=1100 + 2 x (190 +1)
=1100 + 2 x 190 + 2
=1100 + 380 + 2
=1482

Không đăng những câu hỏi tầm thường

\(\left(158x129-158x39\right):18\)

\(=\left[158\left(129-39\right)\right]:18\)

\(=158.90:18\)

\(=14220:18\)

\(=790\)

      \(\left(158.129-158.39\right):18\)

\(=\left[158.\left(129-39\right)\right]:18\)

\(=\left[158.90\right]:18\)

\(=14220:28\)

\(=790\)

b: \(\left(-44\right)+25+\left(-15\right)+44\)

\(=\left(-44+44\right)+\left(25-15\right)\)

=0+10

=10

c: \(201+\left(-197\right)+\left(-201\right)\)

\(=\left(201-201\right)+\left(-197\right)\)

=0-197

=-197

d: \(191+\left(-200\right)+91\)

\(=191+91-200\)

\(=91-9\)

=82

d: \(\left(-158\right)+\left[\left(-23\right)+158\right]\)

\(=-158-23+158\)

\(=\left(-158+158\right)-23\)

=0-23

=-23

e: \(\left(-2021\right)-\left[\left(-2021\right)+25\right]\)

\(=-2021+2021-25\)

=0-25

=-25

( 18 + 29 ) + ( 158 − 18 − 29 ) = 18 + 29 + 158 − 18 − 29 = ( 18 − 18 ) + ( 29 − 29 ) + 158 = 0 + 0 + 158 = 158.

 ( 764 - 759 ) + ( 368 - 369 ) 

= 5 - 5 = 10 

b) ( 4172 - 4168 ) - (1873 - 1869 ) 

= 4-4 = 0

a. (368-363) + ( 764-759) 

    = 5+5=10

b. ( 4172-4168)- ( 1873-1869)

   =4-4=0

c. [ 56. (35+18) ] :53

   = [ 56. 53] : 53

    = 2968 : 53

     = 56

d. Giong cau c do ban

158²+58²-116.158

=158²-116.158+58²

=158²-2.58.158+58²

=(158-58)²=100²=10000

 #hoktot<3#

#đề nghị mấy bn lm sau k chép,mik cần công bằng ạ,cảm ơn#

( 158 x 129 - 158 x 39 ) : 180

= [ 158 x ( 129 - 39 ) ] : 180

= [ 158 x 90 ] : 180

= 14220 : 180

= 79

1) ( 158 x 129 - 158 x 39 ) : 180

= [158 x (129 - 39 ) ] : 180

= 158 x 90 : 180

= 158 x ( 90 : 180 )

= 158 x 1/2

= 158 : 2 

= 79.

2)102- 96 +90-84+78-72+66-60+54-48

= ( 102 - 72 ) + ( -96 + 66 ) + ( 90 - 60 ) + ( -84 + 54 ) + ( 78 - 48 )

= 30 - 30 + 30 - 30 + 30 = 30

1) ( 158 x 129 - 158 x 39 ) : 180

= [158 x (129 - 39 ) ] : 180

= 158 x 90 : 180

= 158 x ( 90 : 180 )

= 158 x 1/2

= 158 : 2 

= 79.

2)102- 96 +90-84+78-72+66-60+54-48

= ( 102 - 72 ) + ( -96 + 66 ) + ( 90 - 60 ) + ( -84 + 54 ) + ( 78 - 48 )

= 30 - 30 + 30 - 30 + 30 = 30

a.258           b.1000

a)=258 

b)=1000

a )258

b) 1000

A = \(\dfrac{2}{300}\) + \(\dfrac{6}{300}\) + \(\dfrac{10}{300}\)+.....+ \(\dfrac{202}{300}\) + \(\dfrac{206}{300}\)

A = \(\dfrac{1}{300}\)\(\times\) ( 2 + 6 + 10 +.....+ 202 + 206)

A = \(\dfrac{1}{300}\) \(\times\) ( 206 +2) \(\times\) { ( 206 - 2) : 4 + 1} : 2

A = \(\dfrac{1}{300}\) x 208 x 52 : 2

A = \(\dfrac{1352}{75}\)

B = \(\dfrac{24\times36+24\times64}{12\times135-12\times35}\)

B = \(\dfrac{24\times(36+64)}{12\times(135-35)}\)

B = \(\dfrac{24\times100}{12\times100}\)

B = 2