326:25 .-1000:25. 119:12. 852:25. 286:14 105:25. 180:60. 195:25. .786:30
( 258 + 852 ) x 1000 : 25 =
( 258 +852 ) x 1000 : 25
= 1110 x 1000 : 25
= 1110000 : 25
= 44400
(258+852)*1000:25
=1110*1000:25
=1110000:25
=44400
(258 + 852) x 1000 : 25 = 1110 x 1000 : 25
= 1110000 : 25
= 44400
|-105| - |-25| + |15| - |5|
53.(-7)+47.(-7)+14.(-25)-4.(-25)
|-105|-|-25|+|15|-|5|
= 105 - 25 + 15 - 5
= 80 + 15 - 5
=95 - 5
= 90
53.(-7)+47.(-7)+14.(-25)-4.(-25)
=(-7).[47+53] + -25.(14-4)
= -7 . 100 + -25.10
=-700 + -250
=-950
Nếu đề là tính thì làm như sau :
|-105|-|-25|+|15|-|5|
=105-25+15-5
=(105-25)+(15-5)
=80+10=90
53.(-7)+47.(-7)+14.(-25)-4.(-25)
=(-7).(53+47)+(-25).(14-4)
=(-7).100+(-25).10
=(-700)+(-250)
=-950
Tính:
a) 29 - [16 + 3 . (51 - 49)]
b) 47 - [(45 . 16 - 25 . 12) : 14]
c) 100 - [60 : (125 : 25 - 3 . 5)]
d) 2345 - 1000 : [19 - 5(21 - 18)]
a) 29 - [16 + 3 . (51 - 49)]
= 29 - [ 16 + 3 . 2 ]
= 29 - [ 16 + 6 ]
= 29 - 22
= 7.
b) 47 - [(45 . 16 - 25 . 12) : 14]
= 47 - [ (720 - 300 ) : 14 ]
= 47 - [ 420 : 14 ]
= 47 - 30
= 17.
c) 100 - [60 : (125 : 25 - 3 . 5)]
= 100 - [ 60 : (5 - 3.5) ]
= 100 - [ 60 : ( 5 - 15) ]
= 100 - [60 : (-10) ]
= 100 - (-6)
= 100 + 6
= 106.
d) 2345 - 1000 : [19 - 5(21 - 18)]
= 2345 - 1000 : [ 19 - 5. 3 ]
= 2345 - 1000 : [ 19 - 15 ]
= 2345 - 1000 : 4
= 2345 - 250
= 2095
# HOK TỐT #
a)29-[16 + 3 . (51 - 49)]
=29 - [ 16 + 3 . 2]
=29 - [16 + 6 ]
=29 - 22
=7
b) 47 - [(45 . 16 - 25 . 12) : 14]
= 47 - [( 45 . 16 - 25 .12) : 14]
=47 - [(720 - 300) : 14]
=47 - [420 : 14]
=47 - 30
= 17
c) 100 - [60 : (125 : 25 - 3 . 5)]
= 100 - [ 60 : ( 5 - 15 )]
=100 - [60 : (- 10)]
= 100 - (- 6)
=94
d) 2345 - 1000 : [19 - 5(21 - 18)]
=2345 - 1000 : [ 19 -5 . 3]
=2345 - 1000 : [19 - 15]
= 2345 - 1000 : 4
=2345 - 250
=2095
TL:
a) 29 - [16 + 3 . (51 - 49)]
= 29 - ( 16+3 . 2)
= 20 - ( 16+6)
= 20 - 22
= (-2)
b) 47 - [(45 . 16 - 25 . 12) : 14]
= 47- ( 420:14)
= 47- 30
= 17
c) 100 - [60 : (125 : 25 - 3 . 5)]
= 100 - ( 60: (-10)
= 100 - (-6)
= 106
d) 2345 - 1000 : [19 - 5(21 - 18)]
= 2345 - 1000 : 4
= 2345-250
= 2095
Học tốt
tính hợp lý:
a. 31 . (12 - 25) - 25 (12 - 31)
b. -287 - (326 - 287) + 156
a) 31 . ( 12 - 25 ) - 25 ( 12 - 31 )
= 31 . (-13) - (-19)
= 31. (-32)
= -1
b) -287 - ( 326 - 287 ) + 156
= -287 - 326 + 156
= (-39) + 156
= -117
Hk tốt,
k nhé
a) 31 . (12 - 25) - 25(12 - 31)
= 31 .12 - 31 . 25 - 25.12 + 25 . 31
= (31 . 12 - 25. 12) - (31 . 25 - 25 . 31)
= (31 - 25) . 12 - 0
= 6 . 12 = 72
b) -287 - (326 - 287) + 156
= -287 - 326 + 287 + 156
= (-287 + 287) - (326 - 156)
= 0 - 170
= -170
a) 31 . (12 - 25) - 25(12 - 31)
= 31 .12 - 31 . 25 - 25.12 + 25 . 31
= (31 . 12 - 25. 12) - (31 . 25 - 25 . 31)
= (31 - 25) . 12 - 0
= 6 . 12
= 72
b) -287 - (326 - 287) + 156
= -287 - 326 + 287 + 156
= (-287 + 287) - (326 - 156)
= 0 - 170
= -170
tính giá trị biểu thức
51/60 x 12/17 : 3/10
5/12 : 7/4 - 25/18 : 35/6
51/60 x 12/17 : 3/10= 51/60 x 12/17 x 10/3 = 6120/3060 = 2
5/12 : 7/4 - 25/18 : 35/6 = 5/12 x 4/7 - 25/18 x 6/35 = 5/21 - 5/21 = 0
a)\(=\dfrac{51}{60}\times\dfrac{12}{17}\times\dfrac{10}{3}=\dfrac{6120}{3060}=2\)
b)\(=\dfrac{4}{7}\times\dfrac{7}{4}-\dfrac{25}{18}\times\dfrac{6}{35}=\dfrac{5}{21}-\dfrac{5}{21}=0\)
a/ 2242,82 : 100 + 37411,8 : 1000= ???
b/ 2001 : 25 - 1999 : 25 = ???
c/ ( 2,04 + 3,4 ) : 0,68 = ???
d/ 40,8 : 12 - 2,03 = ???
e/ 60 : 8 x 2,6 = ???
câu 1 :23*75+25*12+180+25*11
câu 2; 25*46+75*84+25*72+34*75
*là nhân nhé
Bài 1.2: Tính nhanh:
5+ 5 + 5 + 5+ 5 + 5 +5+ 5 + 5 +5
25 + 25 + 25 + 25 + 25 + 25 +25 + 25
45 + 45 + 45 + 45 + 15 + 15 + 15 + 15
2 + 4 + 6 + 8 + 10 + 12 + 14 + 16 + 18
125 + 125 + 125 + 125 - 25 - 25 - 25 - 25
5+ 5 + 5 + 5+ 5 + 5 +5+ 5 + 5 +5=5x10=50
25 + 25 + 25 + 25 + 25 + 25 +25 + 25=25x8=200
45 + 45 + 45 + 45 + 15 + 15 + 15 + 15=(45x4)+(15x4)=180+60=240
5+ 5 + 5 + 5+ 5 + 5 +5+ 5 + 5 +5
= 5 x 10
= 50
25 + 25 + 25 + 25 + 25 + 25 +25 + 25
= 25 x 8
= 200
45 + 45 + 45 + 45 + 15 + 15 + 15 + 15
= 45 x 4 + 15 x 4
= 180 + 60
= 240
2 + 4 + 6 + 8 + 10 + 12 + 14 + 16 + 18
= (2 + 18) + (4 + 16) + (8 + 12) + (6 + 14) + 10
= 20 + 20 + 20 + 20 + 10
= 20 x 4 + 10
= 80 + 10
= 90
125 + 125 + 125 + 125 - 25 - 25 - 25 - 25
= 4 x (125 - 25)
= 4 x 100
= 400
(Tick cho mk pls ^^)
C/m:A=25^60-25^59 A chia hết 8,Achia hết 24,A chia hết 1000
Lời giải:
$A=25^{60}-25^{59}=25^{59}(25-1)=24.25^{59}$
$=24.5^{118}\vdots 24$
Mà $24\vdots 8$ nên $A$ cũng chia hết cho $8$
Lại có: $A=24.5^{118}=3.8.5^3.5^{115}=3.1000.5^{115}\vdots 1000$ (đpcm)