a)215+((-38)-(-58))+(90-85)

215+20+5

(215+5)+20

220+20

240

b) (917-417)+65

500+65

565

a: =215-85-38+58+90

=130+90+20

=150+90=240

b: \(=917-417+65=500+65=565\)

c: \(=31-26+2017+38=2060\)

d: \(=54-37+10-54+67=10+30=40\)

e: \(=326-43+174-57=500-100=400\)

a) 54 + ( -37+ 10 -54 + 67)

=54-37+10-54+67

=(54-54)+(-37+67)+10

=30-10

=20

b) ( 326-43)+( 174-57)

=326-43+174-57

=(326+174)+(-43-57)

=500-100

=400

hok tốt

\(\text{a) 54 + ( -37+ 10 -54 + 67)}\)

\(=54+\left(-37\right)+10+\left(-54\right)+67)\)

\(=\left[54+-\left(54\right)\right]+\left[67+\left(-37\right)\right]+10\)

\(=0+40+10=50\)

\(\text{b) ( 326-43)+( 174-57)}\)

\(\text{=326-43+174-57}\)

\(=\left(326+174\right)-\left(43+57\right)\)

\(=500-100=400\)

a) 54 + ( -37+ 10 -54 + 67)

 =54+ (-37)+10-54+67

=54+(-54)+(10+67)+(-37)

=0+77+(-37)

=40

b) ( 326-43)+( 174-57)

=326-43+174-57

=(326+174)+(-43-57)

=500-100

=400

d. 54-54+67-37+10
=40

e. 326+174-43-57
=400

f. 351+149-875-125
=-500

a) (-37) + 14 + 26 + 37

= [(-37) + 37] + (14 + 26)

= 0 + 40 = 40

b) (-24) + 6 + 10 + 24

= [(-24) + 24] + (10 + 6)

= 0 + 16 = 16

c) 15 + 23 + (-25) + (-23)

= [15 + (-25)] + [23 + (-23)]

= (-10) + 0 = -10

d) 60 + 33 + (-50) + (-33)

= [60 + (-50)] + [33 + (-33)]

= 10 + 0 = 10

e) (-16) + (-209) + (-14) + 209

= [(-16)  + (-14)] + [(-209) + 209]

= (-30) + 0 = -30

f) \(-3^2+\left(-54\right)\div\left[\left(-2\right)^8+7\right]\times\left(-2\right)^2\\ =\left(-9\right)+\left(-54\right)\div263\times4\\ =\left(-9\right)+\dfrac{-216}{263}=\dfrac{-2583}{263}\)

a. \(\left[\left(-37\right)+37\right]+\left(14+16\right)\) = 30 

B. \(\left[\left(-24\right)+24\right]+\left(10+6\right)\) = 16

C. \(\left[\left(-23\right)+23\right]+\left(15-23\right)\)= -8

d. \(\left[33-33\right]+\left(60-50\right)\) = 10

e. \(\left(209-209\right)+\left(-16-14\right)\)= -30

1. Tính tổng:

a) (-37) + 14 + 26 + 37 = 40

b) (-24) + 6 + 10 + 24 = 16

c) 15 + 23 + (-25) + (-23) = -10

d) 60 + 33 + (-50) + (-33) = 10

e) (-16) + (-209) + (-14) + 209 = -30

f) -32 + {-54 : [(-2)8 + 7] . (-2)2} = -32 + {-54 : [(-256) + 7] . 4} = -32 + {-54 : (-249) . 4} = -32 + {-54 : (-996)} = -32 + 0 = -32

2. Thực hiện phép tính:

a) (36 + 79) + (145 - 79 - 36) = 115 + 30 = 145

b) 10 - [12 - (-9 - 1)] = 10 - [12 - (-10)] = 10 - [12 + 10] = 10 - 22 = -12

c) (38 - 29 + 43) - (43 + 38) = 52 - 81 = -29

d) 271 - [(-43) + 271 - (-17)] = 271 - [-43 + 271 + 17] = 271 - [245] = 26

3. Tính hợp lý:

a) 31 . (-18) + 31 . (-81) - 31 = -558 + (-2511) - 31 = -3100

b) (-12) . 47 + (-12) . 52 + (-12) = -564 + (-624) + (-12) = -1200

c) 13 . (23 + 22) - 3 . (17 + 28) = 13 . 45 - 3 . 45 = 585 - 135 = 450

d) -48 + 48 . (-78) + 48 . (-21) = -48 + (-3744) + (-1008) = -4800

1. Tính tổng:

a) (-37) + 14 + 26 + 37 = 40

b) (-24) + 6 + 10 + 24 = 16

c) 15 + 23 + (-25) + (-23) = -10

d) 60 + 33 + (-50) + (-33) = 10

e) (-16) + (-209) + (-14) + 209 = -30

f) -32 + {-54 : [(-2)8 + 7] . (-2)2} = -32 + {-54 : [(-256) + 7] . 4} = -32 + {-54 : (-249) . 4} = -32 + {-54 : (-996)} = -32 + 0 = -32

2. Thực hiện phép tính:

a) (36 + 79) + (145 - 79 - 36) = 115 + 30 = 145

b) 10 - [12 - (-9 - 1)] = 10 - [12 - (-10)] = 10 - [12 + 10] = 10 - 22 = -12

c) (38 - 29 + 43) - (43 + 38) = 52 - 81 = -29

d) 271 - [(-43) + 271 - (-17)] = 271 - [-43 + 271 + 17] = 271 - [245] = 26

3. Tính hợp lý:

a) 31 . (-18) + 31 . (-81) - 31 = -558 + (-2511) - 31 = -3100

b) (-12) . 47 + (-12) . 52 + (-12) = -564 + (-624) + (-12) = -1200

c) 13 . (23 + 22) - 3 . (17 + 28) = 13 . 45 - 3 . 45 = 585 - 135 = 450

d) -48 + 48 . (-78) + 48 . (-21) = -48 + (-3744) + (-1008) = -4800

34 + 35 + 36 + 37 - 24 - 25 - 26 - 27

= (34 - 24) + (35 - 25) + (36 - 26) + (37 - 27)

= 10 + 10 + 10 + 10

= 10 x 4

= 40

34+35+36+37-24-25-26-27

=(34-24)+(35-25)+(36-26)+(37-27)

=    10   +  10    +   10   +     10

=10x4

=40

=(34-24)+(35-25)+(36-26)+(37-27)

=10+10+10+10+10

=50

k nhé

34+35+36+37-24-25-26-27

= (34-24)+(35-25)+(36-26)+(37-27)

= 10+10+10+10

= 40

tính tổng sau một cách hợp lý

34+35+36+37-24-25-26-27

=(34-24)+(35-25)+(36-26)+(37-27)

=10+10+10+10

=40

\(a,\dfrac{-19}{34}-\left(\dfrac{31}{51}-\dfrac{54}{35}\right)=\dfrac{-19}{34}-\left(-\dfrac{1669}{1785}\right)=\dfrac{79}{210}\\ b,\dfrac{-2}{5}.\dfrac{4}{15}+\left(-0,4\right).\dfrac{26}{15}=-\dfrac{8}{75}-\dfrac{52}{75}=-\dfrac{4}{5}\)