Thực hiện phép tính
a/ 127-18.(5+4) e/ 3.(-4)2+2(-5)-20
b/ 4.52-3(24-9) f/ 75-5(15-40)-(-60)
c/ (15-20)+145 g/ 136-(-7)+6-23-36
d/ 375-455-100+550-370
Thực hiện phép tính
a/ 127-18.(5+4) e/ 3.(-4)2+2(-5)-20
b/ 4.52-3(24-9) f/ 75-5(15-40)-(-60)
c/ (15-20)+145 g/ 136-(-7)+6-23-36
d/ 375-455-100+550-370
1, Thực hiện phép tính ( tính hợp lý nếu có thể) A, -1/12+4/3 B,(-4/14-3/15)-(1/5-20/35- -1)7 C, 3/5+ -5/20+30/75+ -7/4 D, 5/6. -12/13 + 7/13 E, 2/-9 - 5/-36 - 1/4 F, 2/23 +-5/12+7/18+21/23+ -7/12
c) Ta có: \(\dfrac{3}{5}+\dfrac{-5}{20}+\dfrac{30}{75}+\dfrac{-7}{4}\)
\(=\dfrac{3}{5}+\dfrac{2}{5}+\dfrac{-1}{4}+\dfrac{-7}{4}\)
\(=1-2=-1\)
Giải:
a)-1/12+4/3=-1/12+16/12=15/12=5/4
b)(-4/14-3/15)-(1/5-20/35-(-1)).7
=-17/35-22/35.7
=-17/35-22/5
=-171/35
c)3/5+-5/20+30/75+-7/4
=3/5+-1/4+2/5+-7/4
=(3/5+2/5)+(-1/4+-7/4)
=1+-2
=-1
d)5/6.-12/14+7/13
=-5/7+7/13
=-16/91
e)2/-9-5/-36-1/4
=-1/12-1/4
=-1/3
f)2/23+-5/12+7/18+21/23+-7/12
=(2/23+21/23)+(-5/12+-7/12)+7/18
=1+-1+7/18
=7/18
a)\(\left(-3\right).8.\left(-2\right).5=\left(-3\right).\left(-2\right).8.5\)
\(=6.40=240\)
b)\(127-18.\left(5+6\right)=127-18.11\)
\(=127-198=-71\)
c)\(125-\left(-75\right)+32-\left(48+32\right)=125+75+32-48-32\)
\(\left(125+75\right)+\left(32-32\right)-48=200-48=152\)
d)\(3.\left(-4\right).2+2.\left(-5\right)-20=-12.2+2.\left(-5\right)-20\)
\(=\left(-12-5\right).2-20=-17.2-20=-140-20=-160\)
Chúc bạn học tốt
thực hiện phép tính sau ( tính hợp li nếu có thể )
a) ( -25 ) + 276 - (276 - 25)
b) 24 x 46 + 24 x 53 + 24
c) 145 + 20 - 45 + 180
d) 12 x 36 + 12 x 65 - 12
e) 3 x 5^2 + 15 x 2^2 - 1^2 x 3
f) 5 x 3^2 - 4 x 2^3 + 35 : 7
GIÚP VỚI Ạ
a, (-25) + 276 - (276 - 25)
= (-25) + 276 - 276 + 25
= [ (-25) + 25] - (276 - 276)
= 0 - 0
= 0
b, 24 x 46 + 24 x 53 + 24
= 24 x ( 46 + 53 + 1)
= 24 x 100
= 2400
c, 145 + 20 - 45 + 180
= (145 - 45) + (20 + 180)
= 100 + 200
= 300
d; 12 x 36 + 12 x 65 - 12
= 12 x ( 36 + 65 - 1)
= 12 x (100)
= 1200
Thực hiện phép tính:
a) 3/2.7/2+5/3.1/2
b) 1/9.2/145-13/3.2/145+2/145
c) (-91/12):15/7-1/18:15/7+20/9:15/7)
a) \(\frac{3}{2}.\frac{7}{2}+\frac{5}{3}.\frac{1}{2}=\frac{21}{2}+\frac{5}{6}=\frac{63}{6}+\frac{5}{6}=\frac{68}{6}=\frac{34}{3}\)
b) \(\frac{1}{9}.\frac{2}{145}-\frac{13}{3}.\frac{2}{145}+\frac{2}{145}=\frac{2}{145}\left(\frac{1}{9}-\frac{39}{9}+\frac{9}{9}\right)=\frac{2}{145}\left(-29\right)=-0.4\)
c) \(\left(-\frac{91}{12}\right):\frac{15}{7}-\frac{1}{18}:\frac{15}{7}+\frac{20}{9}:\frac{15}{7}=\frac{7}{15}\left(-\frac{91}{12}-\frac{1}{18}+\frac{20}{9}\right)=\frac{7}{15}\left(-\frac{65}{12}\right)=-\frac{91}{36}\)
Thực hiện phép tính : a) (9 và 4/9+5 và 2/3)-5 và 1/2 b) 13/9.15/4-13/9.7/4-13/9.5/4 c) 2/3+5/8-(-1)/3+0,375 d) 75%-3 và 1/2+1,5:10/7 e) 1 và 13/15.(0,5)^2.3+(8/15-1 và 19/60):1 và 23/24
Giải:
a) \(\left(9\dfrac{4}{9}+5\dfrac{2}{3}\right)-5\dfrac{1}{2}\)
\(=\left(\dfrac{85}{9}+\dfrac{17}{3}\right)-\dfrac{11}{2}\)
\(=\dfrac{136}{9}-\dfrac{11}{2}\)
\(=\dfrac{173}{18}\)
b) \(\dfrac{13}{9}.\dfrac{15}{4}-\dfrac{13}{9}.\dfrac{7}{4}-\dfrac{13}{9}.\dfrac{5}{4}\)
\(=\dfrac{13}{9}.\left(\dfrac{15}{4}-\dfrac{7}{4}-\dfrac{5}{4}\right)\)
\(=\dfrac{13}{9}.\dfrac{3}{4}\)
\(=\dfrac{13}{12}\)
c) \(\dfrac{2}{3}+\dfrac{5}{8}-\dfrac{-1}{3}+0,375\)
\(=\left(\dfrac{2}{3}-\dfrac{-1}{3}\right)+\left(\dfrac{5}{8}+\dfrac{3}{8}\right)\)
\(=1+1\)
\(=2\)
d) \(75\%-3\dfrac{1}{2}+1,5:\dfrac{10}{7}\)
\(=\dfrac{3}{4}+\dfrac{7}{2}+\dfrac{3}{2}:\dfrac{10}{7}\)
\(=\dfrac{3}{4}+\dfrac{7}{2}+\dfrac{21}{20}\)
\(=\dfrac{53}{10}\)
e) \(1\dfrac{13}{15}.\left(0,5\right)^2.3+\left(\dfrac{8}{15}-1\dfrac{19}{60}\right):1\dfrac{23}{24}\)
\(=\dfrac{28}{15}.\dfrac{1}{4}.3+\left(\dfrac{8}{15}-\dfrac{79}{60}\right):\dfrac{47}{24}\)
\(=\dfrac{7}{5}+\dfrac{-47}{60}:\dfrac{47}{24}\)
\(=\dfrac{7}{5}+\dfrac{-2}{5}\)
\(=1\)
1: Thực hiện phép tính
a: -14. ( 13-57)+57.(10-145)
b: -38.(25-4)+(25.(-4+38)
c: -39.(5-99)+99.(10-39)
2: Tính nhanh
a: 32+(-149)+(-311)+(-89)+(-51)
b: 17-452-548
c: 31+53-431
d: 8-(2014-2008)+2014
e: 1268-(78+1268)-(-78)
f: -48795-(489-48795)+4
g: (-33+180-75)-(180+25)
3: Tìm x€ Z, biết:
a: -2x -40= (5-x)- (-15+60)
b: 2.(x-5)- 3.(x +7)=14
c: -7.(5-x) - 2.(x-10)=15
d: 5.(x-6)-2.(x+3)=12
e: 3.(x-6)- (8-x)= 12
f: 4.(x-5)- (x+7)= -19
g: 7.(x-3)-5.(3-x) =11-15
h: x+18= 6-2x
i: 259-51|4x +3|= (-10)^2.3 +10^1
k: x+15= 20- 4x
l: -12+ x = 5x-20
mik nghĩ chắc trả ai rảnh để trả lời hết đâu dù biết làm
Thực hiện phép tính rồi phân tích kết quả ra thừa số nguyên tố:
a, 75 + 58.50 – 58.25
b, 20: 2 2 – 5 9 : 5 8
c, 5 19 : 5 17 - 4 : 7
d, 47 - 45 . 2 4 - 5 2 . 12 : 14
e, 10 2 : 60 : 5 6 : 5 4 - 3 . 5
f, 2345 - 1000 : 19 - 2 21 - 18 2
g, 500 – {5.[409 – 2 3 . 3 - 21 2 ]+ 10 3 }:15
h, 967 – [8 + 2 . 3 2 – 24:6 + 9 - 7 3 ].5
a, 75 + 58.50 – 58.25 = 3.25 + 58.(50 – 25) = 3.25 + 58.25 = 25.(3+58) = 25.61 = 1525
Ta có: 1525 = 5 2 . 61
b, 20: 2 2 – 5 9 : 5 8 = 20:4 – 5 = 5 – 5 = 0
c, 5 19 : 5 17 - 4 : 7 = 5 2 - 4 : 7 = (25 – 4):7 = 3
d, 47 - 45 . 2 4 - 5 2 . 12 : 14 = 47 – (45.16 – 25.12):14 = 47 – (720 – 300):14 = 47 – 420:14 = 47 – 30 = 17
e, 10 2 : 60 : 5 6 : 5 4 - 3 . 5 = 100 – 60: 5 2 - 15 = 100 – 60:(25 – 15) = 100 – 60:10 = 100 – 6 = 94
Ta có: 94 = 2.47
f, 2345 - 1000 : 19 - 2 21 - 18 2 = 2345 – 1000:(19 – 2. 3 2 ) = 2345 – 1000:(19 – 2.9) = 2345 – 1000:(19 – 18) = 2345 – 1000:1 = 2345 – 1000 = 1345
Ta có: 1345 = 3.269
g, 500 – {5.[409 – 2 3 . 3 - 21 2 ]+ 10 3 }:15 = 500 – {5.[409 – 8 . 3 - 21 2 ]+1000}:15 = 500 – {5.[409 – 3 2 ]+1000}:15 = 500 – {5.(409 – 9)+1000}:15 = 500 – {5.400+1000}:15 = 500 – (2000+1000):15 = 500 – 3000:15 = 500 – 200 = 300
Ta có: 300 = 2 2 . 3 . 5 2
h, 967 – [8 + 2 . 3 2 – 24:6 + 9 - 7 3 ].5 = 967 – [8+2.9 – 4+8].5 = 967 – 30.5 = 967 – 150 = 817
Ta có: 817 = 19.43
Thực hiện phép tính:
A) 7/38 x 9/11 +7/38 x 4/11 -7/38 x 2/11
B) 5/31 x 21/25 + 5/31 x -7/10 - 5/31 x 9/20
C) ( -2/3 + 3/7 ) : 4/5 + (-1/3 + 4/7 ) : 4/5
D) 5/9 : ( 1/11 -5/22 ) + 5/9 : ( 1/15 - 2/3 )
E) 3/14 : 1/28 -13/21 : 1/28 + 29/42 : 1/28 - 8
F) ( -40/51 x 0,32 x17/20) : 64/75
Đây là dấu x ( là nhân ) mọi người nhé
mong mn giúp em ạ
A) 7/38 x 9/11 +7/38 x 4/11 -7/38 x 2/11
=7/38.(9/11+4/11-2/11)
=7/38
B) 5/31 x 21/25 + 5/31 x -7/10 - 5/31 x 9/20
=5/31.(21/25-7/10-9/20)
=5/31.(-31/100)
=-1/20