a, 3.7.23 - 21.(-17)

= 21.23  + 21.17

= 21.(23 + 17)

= 21.40

= 840

b, 7.6.3 - 7.[(-34) + 18)]

= 7.18 - 7.18 + 34.7

= 34.7

= 238

c, 71.64 + 32.(-7) - 13.32

= 71. 32 . 2 - 7.32 - 32. 13

= 32.(71.2 - 7 - 13)

= 32. (142 - 20)

= 32.122

=  3904

d, 13.(23 - 17) - 13.(23 + 17)

= 13.23 - 13.17 - 13.23 - 13.17

= (13.23 - 13.23) - (13.17 + 13.17)

= - 2.13.17

= - 26.17

= -442

e, (29 - 9).(-9) + (-13 - 7).21

= 20.(-9) - 20.21

= -20.(9 + 21)

= -20.30

= - 600

= 3904

3904

 3904

a. 49.51- 49.4 -51.49 -51.4

= -49.4 - 51.4

=4.(-49-51)

=4.-100

=-400

b.71.64 + 32.(-7) -13.32

= 71.64 + 32.(-7-13)

=71.64 + 32.-20 

=71.32.2 +32.-20

=32.(71x2-20)

=32. 122

= 3904

c. (11-13)+(15-17)+..+(59-61)

=-2 x 13

=-26

\(\text{71.64+32.(-7)-13.32}\)

`71.64+32.(-7)-13.32`

`=71.2.32+32.(-7)-13.32`

`=142.32+32.(-7)-13.32`

`=32.[142+(-7)-13]`

`=32.122`

`=390`4

a, (-17)  + 21 + 79 + 17

= (-17 + 17) + (21 + 79)

= 0 + 100

= 100

b, 40 + 22 + (-16)  + (-44)

= 40 + {(-16) + (-44} + 22

= 40 - 60 + 22

= - 20 + 22

= 2 

c, (-12) + (-47) + (-28) + 47

=  - (12 + 28) + (-47 + 47)

= - 40 + 0
= - 40

d, (- 5) + (-3) + 35 + (-17)

= (-5 + 35) - (3 + 17)

=  30 - 20

=  10 

e, 21.23 - 3.7.(-17)

= 21.23 + 21.17

= 21.(23 + 17)

= 21. 40

= 840 

=-7x50=-350

a) 463+318+137+22

 = (463+137)+(318+22)

 =  600+340

 = 940

b) 185.32-32.85

 =  32.(185-85)

 =  32 . 100

 =  3200

c) \(15:\left\{390:\left[500-\left(125+35.7\right)\right]\right\}\)

\(\text{= }15:\left\{390:\left[500-\left(125+245\right)\right]\right\}\)

\(\text{= }15:\left\{390:\left[500-370\right]\right\}\)

\(=15:\left(390:130\right)\)

\(\text{= }15:3\)

\(\text{= }5\)

a)\(463+318+137+22\)

\(=\left(463+137\right)+\left(318+22\right)\)

\(=600+340=940\)

b)\(185.3^2-3^2.85\)

\(=3^2.\left(185-85\right)\)

\(=9.100=900\)

c)\(15:\left\{390:\left[500-\left(125+35.7\right)\right]\right\}\)

\(=15:\left\{390:\left[500-\left(125+245\right)\right]\right\}\)

\(=15:\left\{390:\left[500-370\right]\right\}\)

\(=15:\left\{390:130\right\}\)

\(=15:3=5\)

a) 463 + 318 + 137 + 22 = (463 + 137) + (318 +22) = 600 + 340 = 940

b) 36 : 3 2 + 3 2 . 2 3  -150

= 36 : 9 + 9 . 8 – 1 = 4 + 72 – 1 = 76 – 1 = 75

\(=\dfrac{75:25}{100:25}+\dfrac{18}{21}+\dfrac{19}{32}+\dfrac{1}{4}+\dfrac{3}{21}+\dfrac{13}{32}\\ =\left(\dfrac{3}{4}+\dfrac{1}{4}\right)+\left(\dfrac{18}{21}+\dfrac{3}{21}\right)+\left(\dfrac{19}{32}+\dfrac{13}{32}\right)\\ =1+1+1=3\)

= (19/32+13/32) + (18/21+3/21) + 75/100+1/4

= 1+1+75/100+1/4

= 2+75/100+1/4

= 11/4+1/4

= 3

Đáp án là 3 nha em