Tính :
2 . 17 . 12 + 4 . 6 . 21 + 8 . 3 . 62
37 . 24 + 37 . 76 + 63 . 79 + 63 . 21
24 . 5 - [131 [(13 - 4)2]
21 . 64 - 34 . 21 + 30 . 79
nhanh gấp lắm nha các bn !
1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19+20+21+22+23+24+25+26+27+28+29+30+31+32+33+34+35+36+37+38+39+40+41+42+43+44+45+46+47+48+49+50+51+52+53+54+56+57+58+59+60+61+62+63+64+65+66+67+68+69+70=?
1 * 2 * 3 * 4 * 5 * 6 * 7 * 8 * 9 * 10 * 11 * 12 * 13 * 14 * 15 * 16 * 17 * 18 * 19 * 20 * 21 * 22 * 23 * 24 * 25 * 26 * 27 * 28 * 29 * 30 * 31 * 32 * 33 * 34 * 35 * 36 * 37 * 38 * 39 * 40 * 41 * 42 * 43 * 44 * 45 * 46 * 47 * 48 * 49 * 50 * 51 * 52 * 53 * 54 * 55 * 56 * 57 * 58 * 59 * 60 * 61 * 62 * 63 * 64 * 65 * 66 * 67 * 68 * 69 * 70 * 71 * 72 * 73 * 74 * 75 * 76 * 77 * 78 * 79 * 80 * 81 * 82 * 83 * 84 * 85 * 86 * 87 * 88 * 89 * 90 * 91 * 92 * 93 * 94 * 95 * 96 * 97 * 98 * 99 * 100 bằng bao nhiêu?
37×24+37×76+63×79+21×63
= 37 × 24 + 37 × 76 + 63 × 79 + 21 × 63
= 37 x (24 + 76) + 63 x (79 + 21)
= 37 x 100 + 63 x 100
= (37 + 63) x 100
= 100 x 100
= 10 000
37 x 24 + 37 x 76 + 63 x 79 + 21 x 63
=37 x (24 + 76) + 63 x (79 + 21)
=37 x 100 + 63 x 100
=100 x ( 37 + 63 )
=100 x 100
=10000
Thuc hien phep tinh hop li(neu co the):
1) 3.52 - 16 : 22
2) 23 .17 -23 . 14
3) 17.85 + 15.17 - 120
4) 20 - [30-(5 - 1)2]
5) 36 . 32 + 23 .22
6) 17 .85 + 15.17 - 120 + 20120
7) 37. 24 + 37. 76 + 63 . 79 + 21. 63
1) 3.52 - 16 : 22
= 3 . 25 - 24 : 22
= 75 - 22
= 75 - 4
= 71
2) 23 .17 -23 . 14
= 23 . ( 17 - 14 )
= 8 . 3
= 24
3) 17.85 + 15.17 - 120
= 17 . ( 85 + 17 ) - 120
= 75 . 102 - 120
= 7650 - 120
= 7530
4) 20 - [30-(5 - 1)2]
= 20 - ( 30 - 42 )
= 20 - ( 30 - 16 )
= 20 - 14
= 6
5) 36 . 32 + 23 .22
= 38 + 25
= 6561 + 32
= 6593
6) 17 .85 + 15.17 - 120 + 20120
= 17 . ( 85 + 15 ) - 120 + 1
= 17 . 100 - 120 + 1
= 1700 - 120 + 1
= 1580 + 1
= 1581
7) 37. 24 + 37. 76 + 63 . 79 + 21. 63
= 37 . ( 24 + 76 ) + 63 . ( 79 + 21 )
= 37 . 100 + 63 . 100
= 100 . ( 37 + 63 )
= 100 . 100
= 10000
1) \(3.5^2-16.2^2=3.25-16.4=75-64=11\)
2) \(2^3.17-2^3.14=2^3.\left(17-14\right)=8.3=24\)
3) \(17.85+15.17-120=17.\left(85+15\right)-120\)
\(=17.100-120=1700-120=1580\)
4)\(20-\left[30-\left(5-1\right)^2\right]=20-\left[30-4^2\right]\)
\(=20-\left[30-16\right]=20-14=6\)
5) \(3^6.3^2+2^3.2^2=3^8+2^5=6561+32=6593\)
6) \(17.85+15.17-120+2012^0=17.\left(85+15\right)-120+1\)
\(=17.100-119=1700-119=1581\)
7) \(37.24+37.76+63.79+21.63\) \(=37.\left(24+76\right)+63.\left(79+21\right)\)
\(=37.100+63.100=100.\left(37+63\right)=100.100=10000\)
Sửa lại câu 1 :
\(3.5^2-16:2^2=3.25-16:4\)
\(=75-4=71\)
e, 37 . 24 + 37 . 76 + 63 .79 + 63 . 21
37 . 24 + 37 . 76 + 63 .79 + 63 . 21
= 37 . ( 24 + 76 ) + 63 . ( 79 + 21 )
= 37 . 100 + 63 . 100
= ( 37 + 63 ) . 100
= 100 . 100
= 10000
e, 37 . 24 + 37 . 76 + 63 .79 + 63 . 21
= 37 . ( 24 + 76 ) + 63 . ( 79 + 21 )
= 37 . 100 + 63 . 100
= 100 . ( 37 + 63 )
= 100 . 100
= 1002
37 . 24 + 37 . 76 + 63 . 79 + 63 . 21
= 37 ( 24 + 76 ) + 63 ( 79 + 21 )
= 37 . 100 + 63 . 100
= 100 ( 37 + 63 )
= 100 . 100
= 10000
Bài 2 : Tính nhanh
a ) ( 8 , 7 x 29 + 8, 7 x 35 ) : 64
b ) 372 x 9 + 372
c ) 37 x 24 + 37 x 76 + 63 x 79 + 63 x 21
d ) 42 x 53 + 47 x 156 - 47 x 114
giúp mk nha . Làm ơn nhanh lên nhé
Thannks
Bài 2 : Tính nhanh
a ) ( 8 , 7 x 29 + 8, 7 x 35 ) : 64
= [ 8.7 x ( 29 + 35 ) ] : 64
= [ 8.7 x 64 ] : 64
= 8.7
b ) 372 x 9 + 372
= 372 x ( 9 + 1 )
= 372 x 10
= 3720
c ) 37 x 24 + 37 x 76 + 63 x 79 + 63 x 21
= 37 x ( 24 + 76 ) + 63 x ( 79 + 21 )
= 37 x 100 + 63 x 100
= 100 x ( 37 + 63 )
= 100 x 100
= 10000
d ) 42 x 53 + 47 x 156 - 47 x 114
= 42 x 53 + 47 x ( 156 - 114 )
= 42 x 53 + 47 x 42
= 42 x ( 53 + 47 )
= 42 x 100
= 4200
hok tốt nha
a) (8,7 x 29 + 8,7 x 35) : 64
= [8,7 x (29 + 35)] : 64
= (8,7 x 64) : 64
= 8,7 x (64 : 64)
= 8,7 x 1 = 8,7
b) 372 x 9 + 372 = 372 x (9 + 1)
= 372 x 10 = 3720
c) 37 x 24 + 37 x 76 + 63 x 79 + 63 x 21
= 37 x (24 + 76) + 63 x (79 + 21)
= 37 x 100 + 63 x 100
= (37 + 63) x 100
= 100 x 100 = 10000
d) 42 x 53 + 47 x 156 - 47 x 114
= 42 x 53 + 47 x (156 - 114)
= 42 x 53 + 47 x 42
= 42 x (53 + 47)
= 42 x 100
= 4200
a ) ( 8 , 7 x 29 + 8, 7 x 35 ) : 64
= [ 8,7 x ( 29 + 35 ) ] : 64
= 8,7 x 64 : 64
= 8,7
b ) 372 x 9 + 372
= 372 x ( 9 + 1 )
= 372 x 10
= 3720
c ) 37 x 24 + 37 x 76 + 63 x 79 + 63 x 21
= [ 37 x ( 24 + 76 ) ] + [ 63 x ( 79 + 21 ) ]
= [ 37 . 100 ] + [ 63 x 100 ]
= 3700 + 6300
= 10000
d ) 42 x 53 + 47 x 156 - 47 x 114
= 42 x 53 + 47 x ( 156 - 114 )
= 42 x 53 + 47 x 42
= 42 x ( 53 + 47 )
= 42 x 100
= 4200
1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19+20+21+22+23+24+25+26+27+28+29+30+31+32+33+34+35+36+37=
1+2+3+4+5+6+7+8+9+10+11+12+13+14+15+16+17+18+19+20+21+22+23+24+25+26+27+28+29+30+31+32+33+34+35+36+37
=(1+37)x37:2
=703
Bài 1: Bỏ dấu ngoặc rồi tính:
1) 40 + 15 + (-10) + (-15)
2) -13 + (-750) + (-17) + 750
3) (35 – 17) + (17 + 120 – 35)
4) (55 + 45 + 15) – (15 – 55 + 45)
5) – (12 + 21 – 23) – (23 – 21 + 10)
6) (2020 – 79 + 15) – (- 79 + 15)
7) – (515 – 80 + 91) – (2010 + 80 – 91)
8) 25 – (–17) + 24 – 12
9) 235 – (34 + 135) – 100
10) (13 + 49) – (13 – 135 + 49)
Tớ đang cần gấp. Các bạn giúp tớ nhé. Tớ cảm ơn
1) 40 + 15 + (-10) + (-15) 2) -13 + (-750) + (-17) + 750 3) (35 - 17) + (17 + 120 - 35)
= 40 + 15 - 10 - 15 = -13 - 750 - 17 + 750 = 35 - 17 + 17 + 120 - 35
= (40 - 10) + (15 - 15) = (-13 - 17) + (-750 + 750) = (35 - 35) + (-17 + 17) + 120
= 30 = -30 = 120
4) (55 + 45 + 15) - (15 - 55 + 45) 5) -(12 + 21 - 23) - (23 - 21 + 10) 6) (2020 - 79 + 15) - (-79 + 15)
= 55 + 45 + 15 - 15 + 55 - 45 = -12 -21 + 23 - 23 + 21 - 10 = 2020 - 79 + 15 + 79 - 15
= (45 - 45) + (15 - 15) + (55 + 55) = (-12 - 10) + (-21 + 21) + (23 - 23) = 2020 + (-79 + 79) + (15 - 15)
= 110 = -22 = 2020
7) -(515 - 80 + 91) - (2010 + 80 - 91) 8) 25 - (-17) + 24 - 12 9) 235 - (34 + 135) - 100
= -515 + 80 - 91 - 2010 - 80 + 91 = 25 + 17 + 24 - 12 = 235 - 34 - 135 - 100
= (-515 -2010) + (80 - 80) + (-91 + 91) = 54 = -34
= -2525
10) (13 + 49) - (13 - 135 + 49)
= 13 + 49 - 13 + 135 - 49
= (13 - 13) + (49 - 49) +135
= 135