a,15+x+27+53=100 b, 207<x+17<210
tìm x thuộc n biết:
a) 1260 : [ 207 - ( 10x - 7 )] = 15
b) 1236 nhân ( 3x - 15 ) = 0
c) [ 53 + ( 132 - x ) ] :23 = 8
d) 125 - 5 ( 17 - x ) = 100
e) x - 24 :6 = 12
làm nhanh, đúng mik tick luôn nhé.
a) 207-10x+7=84
10x=130
x=13
b)=> 3x-15=0
3x=15
x=5
c) 53+132-x=184
132-x=131
x=1
d) 85-5x=25
5x=60
x=12
e) x-4=12
x=16
a/ 1260: [207-(10x-7)]=15
207-(10x-7) =1260:15= 84
10x-7= 207-84=123
10x=123+7=130
x= 130:10=13
b/1236.(3x-15)=0
3x-15= 0:1236=0
3x =0+15=15
x =15:3=5
c/[53+(132-x)]:23=8
53+(132-x) =8.23=184
132-x =184-53=131
x =132-131=1
d/ 125-5(17-x)=100
17-x= 100:(125-5)=5/6
17-5/6=97/6
e/ x-24:6=12
x-4=12
x=12+4=16
Tìm x
15+x+27+53=100. X-36-38=239
Ko chắc nhé !!! ^_^
15+x+27+53=100. x-36-38=239
x + ( 15 + 27 + 53 ) = 100 x - 36 = 239 + 38
x + 95 = 100 x - 36 = 277
x = 100 - 95 x = 277 + 36
x = 5 x = 313
Tìm x, biết:
a ) 2 5 . x + 1 3 = 1 5 b ) 4 9 − 5 3 . x = − 2 c ) 1 5 + 5 3 : x = 1 2 d ) 5 7 : x − 3 = − 2 7
Tìm x, biết:
a ) 2 5 . x + 1 3 = 1 5 b ) 4 9 − 5 3 . x = − 2 ; c ) 1 5 + 5 3 : x = 1 2 d ) 5 7 : x − 3 = − 2 7
a ) x = 1 3 . b ) x = 22 15 . c ) x = 50 9 . d ) x = 5 19 .
Câu 1.Thực hiện phép tính (bằng cách hợp lí nếu có thể)
a) 53.(-15) + (-15).47
b) 43 (53 – 81) + 53 (81 – 43)
Câu 2:Liệt kê rồi tính tổng các số nguyên x thỏa mãn :
- 20 < x < 20
Câu 3. Tìm số nguyên x biết:
a) – 2x – 8 = 72
b)|x-2|= 27
Thực hiện phép tính :
a) 123 - 27 + 27 + 13 - 123
b) 175 + 25 + 13 + 15 - 175 - 25
c) 53 x 39 + 47 x 39 + 53 x 21 + 47 x 21
d) 49 x 35 + 49 x 16 - 49 x 61
a) `123 - 27 + 27 + 13 - 123`
`= (123 - 123) + (27 - 27) + 13`
`= 0 + 0 + 13`
`= 13`
`---`
b) `175 + 25 + 13 + 15 - 175 - 25`
`= (175-175)+(25-25)+25+13`
`=0+0+25+13`
`=28`
`---`
c) \(53\times39+47\times39+53\times21+47\times21\)
\(=\text{[}\left(53+47\right)\times39]+\left[\left(53+47\right)\times21\right]\)
\(=\left(100\times39\right)+\left(100\times21\right)\)
\(=3900+2100\)
`=6000`
`---`
d) \(49\times35+49\times16-49\times61\)
`=` \(49\times\left(35+16-61\right)\)
`=` \(49\times\left(-10\right)\)
`=-490`
tính nhanh
3) 14.35.5+10.25.7+20.7
4) 15(27+18+6)+ 15(23.12)
5) 24(15+49)+12(50+42)
6) 10(81+19)+100+50(91+9)
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
giúp mik nhé các bạn mong các bạn giúp đỡ
5) 24*(15+49)+12*(50+42)
=24*64+12*92
=24*64+12*2*46
=24*64+24*46
=24*(64+46)
=24*110
=2640
7) 53*( 51+4)+53*(49+96)+53
=53*55+53*145+53
=53*(55+145)+53
=53*200+53
10600+53
=10653
bài 1: tính nhanh
14.35.5+10.25.7+20.70
15.(27+18+6) + 15.(23+12)
24.15+49) + 12.(50+42 )
10.(81+19) + 100 + 50 .(91+9)
53.(51 +4) +53 .( 49+96) 53
nói chung là lên gg mà sợt;vvv
Tính một cách hợp lí
a) 13.58.4+32.26.2+52.10
b)14.35.5+10.25.7+20.70
C) 15.(27+18+6)+15.(23+12)
d) 53.(51+4)+53.(49+96)+53
e)15.37.4+120.21+21.5.12
a) \(\text{13 x 58 x 4 + 32 x 26 x 2 + 52 x 10 }\)
\(\text{=(13 x 4 ) x 58 + 32 x 13 x 2 x 2 + 13 x 4 x 10}\)
\(\text{= ( 13 x 4 ) x 58 + 32 x ( 13 x 2 x 2 ) + ( 13 x 4 ) x 10 }\)
\(\text{= 52 x 58 + 32 x 52 + 52 x 10}\)
\(\text{=52 x ( 58 + 32 + 10 )}\)
\(\text{=52 x 100 = 5200}\)
b) \(\text{14 x 35 x 5 + 10 x 25 x 7 + 20 x 70 x 2}\)
\(\text{= ( 14 x 5 ) x 35 + (10 x 7 ) x 25 + 20 x 70 x 2 }\)
\(\text{= 70 x 35 + 70 x 25 + 20 x 2 x 70 }\)
\(\text{= 70 x ( 35 + 25 + 40 )}\)
\(\text{= 70 x 100 = 7000 }\)
e) \(\text{5.3.37.4+5.24.21+21.5.12}\)
\(\text{= 5.(3.37.4+24.21+21.12)}\)
\(\text{= 5.1200}\)
\(=6000\)
a) \(13.58.4+32.26.2+52.10\)
\(=52.58+32.52+52.10\)
\(=52.\left(58+32+10\right)\)
\(=52.100=5200\)
b) \(14.35.5+10.25.7+20.70\)
\(=7.5.35.2+10.7.25+20.70\)
\(=35.70+70.25+20.70\)
\(=70\left(35+25+20\right)\)
\(=70.80=5600\)
c) \(...=15\left(27+18+6+23+12\right)\)
\(=15\left(27+23+18+12+6\right)\)
\(=15\left(50+30+6\right)=15.86=1290\)
d) \(...=53\left(51+4+49+96+1\right)\)
\(=53\left(51+49+4+96+1\right)\)
\(=53\left(100+100+1\right)=53.201=10653\)
e) \(15.37.4+120.21+21.5.12\)
\(=15.4.37+60.2.21+21.60\)
\(=60.37+60.42+21.60\)
\(=60.\left(37+42+21\right)=60.100=6000\)