tính nhanh
a, 4*125*25*8
b,2*3*4*5*50*25
c,8*427*3+6*573*4
d,54*47-47*53-20-27
e,100-47*72-47*28
Tính nhanh:
54 x 113 + 45 x 113 + 113
54 x 47 - 47 x 53 - 20 - 27
10000 - 47 x 72 - 47 x 28
(145 x 99 + 145) - (143 x 101 - 143)
1002 x 9 - 18
8 x 427 x 3 + 6 x 573 x 4
2008 x 867 + 2009 x 133
a/ = 113 x ( 54 + 45 + 1 ) = 113 x 100 = 11300
b/ = 47 x ( 54 - 53 ) - 20 - 27 = 47 - 20 - 27 = 0
c/ = 145 x ( 99 + 1 ) - 143 x ( 101 - 1 ) = 145 x 100 - 143 x 100 = 100 x ( 145 - 143 ) = 100 x 2 = 200
d/ = 1002 x 9 - 2 x 9 = 9 x ( 1002 - 2 ) = 9 x 1000 = 9000
e/ = 24 x 427 + 24 x 573 = 24 x ( 427 + 573 ) = 24 x 1000 = 24000
f/ Sửa đề bài là :
2008 x 867 + 2008 x 133 = 2008 x ( 867 + 133 ) = 2008 x 1000 = 2008000
4. Tỉnh nhanh:
a. 8 * 427 * 3 + 6 * 573 * 4
d. (137 * 99 + 137) - (17 * 101 - 17)
b. 54 * 47 - 47 * 53 - 20 - 27
c. 6 * 1235 * 20 - 5 * 235 * 24
e. (145 * 99 + 145) - (143 * 101 - 143)
g. (2003-123 8:4) x (36:6-6)
Bài 4 : Tính nhanh
a, 8 * 427 *3 + 6 * 573 * 4
b, ( 145 * 99 + 145 ) - ( 143 * 102 - 143 )
c, 54 * 47 - 47 * 53 - 20 - 20 - 27
bài 7:tính nhanh
a (145 x 99+145)-(143 x 102-143) b,54 x 47 - 47 x 53 - 20 -27
c, 10000 - 47 x 72 - 47 x 28 d, 3457 - 27 x 48 - 48 x 73 + 6543
a) \(\left(145\times99+145\right)-\left(143\times102-143\right)\)
\(=\left[145\times\left(99+1\right)\right]-\left[143\times\left(102-1\right)\right]\)
\(=\left(145\times100\right)-\left(143\times101\right)\)
\(=14500-14443\)
\(=57\)
b) \(54\times47-47\times53-20-27\)
\(=47\times\left(54-53\right)-20-27\)
\(=47-20-27\)
\(=0\)
c) \(10000-47\times72-47\times28\)
\(=10000-47\times\left(72+28\right)\)
\(=10000-47\times100\)
\(=10000-4700\)
\(=5300\)
d) \(3457-27\times48-48\times73+6543\)
\(=\left(3457+6543\right)-48\times\left(27+73\right)\)
\(=10000-48\times100\)
\(=10000-4800\)
\(=5200\)
tinh
a, 8*427*3+6*573*4
b, 6*1235*20-5*235*24
c, (145*99+145)-(143*102-143)
d, 54*47-47*53-20-27
giup mn vs
cam on nhiu nhiu
mn can gap nhe
câu c d bạn tự làm nhé tương tự vậy thôi à ( bạn ấn nút đúng giùm nhé )
a.8x427x3+6x573x4
=(8x3)x427+(6x4)x573
=24x427+24x573
=24x(427+573)
=24x1000
=24 000
b.6x1235x20-5x235x24
=(6x20)x1235-(5x24)x235
=120x1235-120x235
=120x(1235-235)
=120x1000
=120 000
c.(145x99+145)-(143x102-143)
=(145x99+145x1)-(143x102-143x1)
=[145x(99+1)]-[143x(102-1)]
=145x100+143x101
=145x100+143x100+143
=100x(145+143)+143
=100x298+143
=29800+143
=29 943
d.54x47-47x53-20-27
=47x(54-53)-20-27
=47x1-20-27
=47-20-27
=27-27
=0
a) 8*427*3+6*573*4=24*427+24*573
=24*(427+573)
=24*1000
=24000
b) 6*1235*20-5*235*24=120*1235-235*120
=120*(1235-235)
=120*1000
=120000
c) (145*99+145)-(143*102-143)=(145*99+145*1)-(143*100+143)
=[145*(99+1)]-(14300+143)
=14500-(14300+143)
=57.
câu c mình nghĩ nếu phép tính thứ hai là 143*101-143 thì sẽ chẵn hơn.
d) 54*47-47*53-20-27=54*47-47*53-(20+27)
=54*47-47*53-47*1
=47*(54-53-1)
=0*47
=0
bài 1 : tính nhanh
(145 x 99 + 145) - (143 x 102 - 143)
54 x 47 - 47 x 53 - 20 - 27
2 x 8 x 50 x 25 x 125
Tính hợp lý:
45-58+(-45)+(+58)-3
(-57)-(-12)+3-(-57)
-(-24)-(-30)+(-24)-30+8
-(-12)+(+19)-(+12)+8-19
47-(-53)+(-47)-(+53)
-(+28)+32-(-28)+(-34)
15-(+72)+(-15)+(+72)
20-(+46)+(-25)-(-46)
28-(-32)+(-28)-32+5
-75+(-49)+(+75)+49-12
Giúp e vs ạ
45-58+(-45)+(+58)-3=45-58-45+58-3=(45-45)+(58-58)-3=-3
(-57)-(-12)+3-(-57)=-57+12+3+57=(-57+57)+12+3=15
-(-24)-(-30)+(-24)-30+8=24+30-24-30+8=(24-24)+(30-30)+8=8
-(-12)+(+19)-(+12)+8-19=12+19-12+8-19=(12-12)+(19-19)+8=8
47-(-53)+(-47)-(+53)=47+53-47-53=(47-47)+(53-53)=0
-(+28)+32-(-28)+(-34)=-28+32+28-34=(-28+28)-(34-32)=-2
15-(+72)+(-15)+(+72)=15-72-15+72=(15-15)+(72-72)=0
20-(+46)+(-25)-(-46)=20-46-25+46=(20-25)+(46-46)=-5
28-(-32)+(-28)-32+5=28+32-28-32+5=(28-28)+(32-32)+5=5
-75+(-49)+(+75)+49-12=-75-49+75+49-12=(-75+75)+(49-49)-12=-12
\(...=45-58-45+58-3=-3\)
\(...=-57+12+3+57=15\)
\(...=24+30-24-30+8=8\)
\(...=12+19-12+8-19=8\)
\(...=47+53-47-53=0\)
\(...=-28+32+28-34=-2\)
\(...=15-72-15+72=0\)
\(...=20-46-25+46=-5\)
\(=...28+32-28-32+5=5\)
\(...=-75-49+75+49-12=-12\)
Bài 1: tính
a) 310 . 315 : 322 + 47 : 44
b) [ ( 52 . 53 ) – 72 . 2 ) : 2 ] . 6 = 7 . 25
c) ( 102022 – 102021 ) : 10
d) ( 142 – [ 50 – (25 . 10 – 23 . 5 ) ]
e){ 210 : [50 – ( 23 . 10 – 23 . 5 ) ] }
f ) 3 + 6 + 9 + ….. + 102
a) 310 . 315 : 322 + 47 : 44
= 3(10 + 15 - 22 ) + 4(7-4)
= 33 + 43
= ( 3.4)3
=123
b)[ (52 . 53 ) - 72 . 2 ) : 2 ] . 6 = 7 . 25
[ (52 . 53 ) - 72 . 2 ) : 2 ] . 6 = 7 . 32
= 224
c) ( 102022 - 102021 ) : 10
Chịu nha vì trừ không có công thức , nếu chia thì được ạ , bạn coi có nhầm phần c k?
a)8x427x3+6x573x4=24x427+24x573=24x(427+573)=24x1000=24000
b)86x27-43x54=43x2x27-43x2x27=0
c)(145x99+145)-(143x101-143)=145x(99+1)-[143x(101-1)]=145x100-143x100=14500-14300=200
d)10000-(47x72+47x2)=10000-[47x(72+2)]=10000-(47x74)=10000-3478=6522
~~~~~~HT~~~~~~