123 -76 56-51 78 - 56
56 -7 x 5 53 -23 42 : 2
tINH NHANH
A ) 78. 123 + 88 .33 - 78 x 23 + 11.8.67
b)42 . 53 + 47.156 _ 114.47
c ) 53 . 39 + 39 . 47 - 15 . 21 - 7 . 155
d ))15 . 37 . 4 + 120 . 21 + 21 x 5 x12
e ) 2 . 53 . 12 4 . 6 . 87 _ 15 . 4
g ) (2500 + 75 ) : 25 - ( 36 . 11 ) : 1
BÀI 3: TÍNH BẰNG CÁCH THUẬN TIỆN NHẤT
245 x 11 + 11 x 365 78 x 75 + 75 x 89 + 75 x 123 2 x 250 x 50 x 8
(76 : 7) x 4 (372 x 15) x 9 (56 x 23 x 4) : 7
Bài 2: Tính hợp lí
a.1152-(374+1152)+(-65+374)
b.[53+(-76)]-[-76-(-53)]
c.-48+48.(-78)+21.(-48)
d.(-12).47(-12).52+(-12)
e.(-1)+(-3)+...(-199)+(-201)
f.17+(-20)+23+(-26)+...+53+(-56)
Mấy bạn giúp mình
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?
tính nhanh nhé
7) 53(51+4)+53(49+96)+53
8)42(15+96)+6(25+4).7
9) 45(13+78)+9(87+22).5
10) 16(27+75)+8(53+25).2
7)
53.(51+4)+53.(49+96)+53
=53.55+53.145+53
=53.(55+145+1)
=53.201
=10653
8)
42.(15+96)+6.(25+4).7
=42.111+(6.7).29
=42.111+42.29
=42.(111+29)
=42.140
=5880
9)
45.(13+78)+9.(87+22).5
=45.91+(9.5).109
=45.91+45.109
=45.(91+109)
=45.200
=9000
10)
16.(27+75)+8.(53+25).2
=16.102+(8.2).78
=16.102+16.78
=16.(102+78)
=16.180
=2880
7)
53.(51+4)+53.(49+96)+53
=53.55+53.145+53
=53.(55+145+1)
=53.201
=10653
8)
42.(15+96)+6.(25+4).7
=42.111+(6.7).29
=42.111+42.29
=42.(111+29)
=42.140
=5880
9)
45.(13+78)+9.(87+22).5
=45.91+(9.5).109
=45.91+45.109
=45.(91+109)
=45.200
=9000
10)
16.(27+75)+8.(53+25).2
=16.102+(8.2).78
=16.102+16.78
=16.(102+78)
=16.180
=2880
23 . (123 - 19 ) + 123 . (19 - 23)
-38 . (78 - 51) -78 . (51 - 38
g)18 . (-24) + 35 . 42 -18 . 76 + 35 . (-142)
h) 104 : (-13) - [ 56 - 220 : ( -4 )]
i)1010: {2500:[ 550 - (4 . 53 - 23 . 25) ]}
j) (72 + 32 . 42 )+(-145 ) + 45 -20230 + 12023
a, 18.(-24) + 35.42 - 18.76 + 35.(-142)
= [ 18.(-24) - 18.76] + (35.42 + 35(-142)]
= -18.[ 24 + 76] - 35.( 142 - 42)
= -18.100 - 35. 100
= - 100.(18 + 35)
= - 100. 53
= - 5300
h, 104 : (-13) - [56 - 220 : (-4)]
= 104 : (-13) - [ 56 + 55]
= -8 - 111
= - 119
j; 1010 : {2500 : [550 - (4.53 - 23.25)]}
= 1010 : {2500 : [550 - (212 - 575)]}
= 1010 : {2500 : [550 + 363]
= 1010 : { 2500 : 913}
= 1010 : \(\dfrac{2500}{913}\)
= 1010 x \(\dfrac{913}{2500}\)
= 368,852
1. Tính
a, 1+7+8+15+23+...+160
b, 17+4+5+9+19+...+60+9
c, 78*3+78*24+78*17*22*72
d, 53*39+47*39+47-53*21-47*21
e, 2*53*12+4*6*87-3*8*40
g, 5*7*77-7*60+49*25-15*42
h, 1*2+2*3+3*4+...+2016*2017
Tính nhanh
13.58.4 + 32.26.2+52.10
15.34.4+120.21+21.5.12
14.35.5+10.25.7+20.70
24.( 15+49)+12.(50+42)
53.(51+4)+53.(49+96)+53
42.(15+96)+6.(25+4).7
45.(13+78)+8.(53+25).2
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