1) Tìm x:
a) x - 5/7 -13/14 = 1
b) 3/4 + x 1 1/5 = 11/3
1 1/5 là hỗn số nhé
1. 15 và 3/9 - (11/13 + 7 và 3/19)
2. (17 và 29/31 - 3 và 7/8) - (2 và 28/31 - 4)
3. (-3/14 + 2/5) : 5/13 + (-11/14 +3/5) x 13/5
mik ko ghi đc hỗn số nên mik ghi "và" nha
3: \(=\dfrac{13}{5}\left(-\dfrac{3}{14}+\dfrac{2}{5}+\dfrac{-11}{14}+\dfrac{3}{5}\right)\)
=0
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
bài 1 :
5/7 : x + 2/3 =" hỗn số" 1 1/3
x* 3/7 - 5/14 = " hỗn số" 2 1/3
3 5/7- x * 1/3 = 1 13 /11
tick cho bạn giải rõ ràng và nhanh nhất nhé>>
Câu 1: \(\frac{5}{7}\):x+\(\frac{2}{3}\)=1\(\frac{1}{3}\)
\(\frac{5}{7}\):x+\(\frac{2}{3}\)=\(\frac{4}{3}\)
\(\frac{5}{7}\):x=\(\frac{4}{3}\) - \(\frac{2}{3}\)
\(\frac{5}{7}\):x=\(\frac{2}{3}\)
x=\(\frac{5}{7}\):\(\frac{2}{3}\)
x=\(\frac{15}{14}\)
Câu 2:x*\(\frac{3}{7}\)-\(\frac{5}{14}\)=2\(\frac{1}{3}\)
x*\(\frac{3}{7}\)-\(\frac{5}{14}\)=\(\frac{7}{3}\)
x*\(\frac{3}{7}\)=\(\frac{7}{3}\)+\(\frac{5}{14}\)
x*\(\frac{3}{7}\)=\(\frac{113}{42}\)
x=\(\frac{113}{42}\):\(\frac{3}{7}\)
x=\(\frac{791}{126}\)
Câu 3: 3\(\frac{5}{7}\)-x*\(\frac{1}{3}\)=1\(\frac{13}{11}\)
\(\frac{26}{7}\)-x*\(\frac{1}{3}\)=\(\frac{24}{11}\)
x*\(\frac{1}{3}\)=\(\frac{26}{7}\)-\(\frac{24}{11}\)
x*\(\frac{1}{3}\)=\(\frac{118}{77}\)
x=\(\frac{118}{77}\):\(\frac{1}{3}\)
x=\(\frac{356}{77}\)
X - 5/7 - 13/14 = 1
3/5 + x + 1 1/5 = 11/3 1 1/5 là hỗn số
a) x - 5/7 - 13/14 = 1
x- (5/7+13/14) = 1
x- 23/14 = 1
x = 37/14
b) \(\frac{3}{5}+x+1\frac{1}{5}=\frac{11}{3}\)
\(\frac{3}{5}+x+\frac{6}{5}=\frac{11}{3}\)
\(\frac{9}{5}+x=\frac{11}{3}\)
x = 28/15
Bài 1: Tính
a) -7/9 . 2/3/4 (2/3/4 là hỗn số : 2 là số nguyên, 3/4 là phân số)
b) 2/3 + 1/3 . (-2/5)
c) 3/4 . 15/1/3 - 3/4 . 43/1/3
d) (-49,1) . 13/27 - 58,9 . 13/27
e) 0,375 : (-4,5)
f) 3/1/7 : (-1/3/7)
g) 9/1/3 : 4/2/3 - 2
h) (7/3/4 : 0,3125 + 4,5 . 2/2/45) : (-8,5)
Bài 2: Tính giá trị biểu thức
A = (-6/11) . 7/10 . (11/-6).(-20)
B = (-1/9) . (-17/29) . 58/51
C = (-3/7) . 5/11 + (-5/14) . 5/11
D = (1/1/27 . 12/23 . 9/14) : (-3/23)
Bài 3: Tìm x
a) 3/7 . x - 2/5 . x = -17/35
b) (3/4 . x -9/16) . [1/3 + (-3/5) : x] = 0
c) (x + 3/5) . (x + 1) = 0
1.
a) \(\frac{-7}{9}.2\frac{3}{4}=\frac{-7}{9}.\frac{11}{4}=\frac{-77}{36}\)
b) \(\frac{2}{3}+\frac{1}{3}.\frac{-2}{5}=\frac{2}{3}+\frac{-2}{15}=\frac{8}{15}\)
c) \(\frac{3}{4}.15\frac{1}{3}-\frac{3}{4}.43\frac{1}{3}=\frac{3}{4}.\frac{46}{3}-\frac{3}{4}.\frac{130}{3}=\frac{23}{2}-\frac{65}{2}=-21\)
d) \(\left(-49,1\right).\frac{13}{27}-58,9.\frac{13}{27}=\frac{13}{27}.\left(-49,1-58,9\right)=\frac{13}{27}.\left(-108\right)=-52\)
e) \(0,375:\left(-4,5\right)=\frac{-1}{12}\)
f) \(3\frac{1}{7}:\left(-1\frac{3}{7}\right)=\frac{22}{7}:\frac{-10}{7}=\frac{-11}{5}\)
g) \(9\frac{1}{3}:4\frac{2}{3}-2=\frac{28}{3}:\frac{14}{3}-2=2-2=0\)
h) \(\left(7\frac{3}{4}:0,3125+4,5.2\frac{2}{45}\right):\left(-8,5\right)=\left(\frac{31}{4}:\frac{5}{16}+\frac{9}{2}.\frac{92}{45}\right):\frac{-17}{2}=\left(\frac{124}{5}+\frac{46}{5}\right):\frac{-17}{2}=34:\frac{-17}{2}=-4\)
Bài 1 : Tính:
a)
\(\frac{-7}{9}.2\frac{3}{4}=\frac{-7}{9}.\frac{11}{4}=\frac{-77}{36}\)
b)
\(\frac{2}{3}+\frac{1}{3}.\frac{-2}{5}=\frac{2}{3}+\frac{-2}{15}=\frac{10}{15}+\frac{-2}{15}=\frac{8}{15}\)
c)
\(\frac{3}{4}.15\frac{1}{3}-\frac{3}{4}.43\frac{1}{3}=\frac{3}{4}.\frac{46}{3}-\frac{3}{4}.\frac{130}{3}\)\(=\frac{23}{2}-\frac{65}{2}=\frac{-42}{2}=-21\)
....
Tự lm tiếp dạng như v
Bài 2 :
\(A=\frac{-6}{11}.\frac{7}{10}.\frac{11}{-6}.-20=\left(\frac{-6}{11}.\frac{11}{-6}\right).\left(\frac{7}{10}.-20\right)\)\(=1.\left(-14\right)=-14\)
.....
Bài 3 :
\(\frac{3}{7}.x-\frac{2}{5}.x=\frac{-17}{35}\)
\(\Leftrightarrow\frac{3}{7}-\frac{2}{5}.x=\frac{-17}{35}\)
\(\Leftrightarrow\frac{1}{35}x=\frac{-17}{35}\)
\(\Leftrightarrow x=\frac{-17}{35}:\frac{1}{35}\)
\(\Leftrightarrow x=\frac{-17}{35}.35=-17\)
Tìm x:
a) 2/5 = 3/4 : x = -1/2
b) 5/7 - 2/3 . x = 4/5
c) 1/2x + 3/5x = -2/3
d) 4/7x - x = -9/14
b: \(\dfrac{5}{7}-\dfrac{2}{3}\cdot x=\dfrac{4}{5}\)
=>\(\dfrac{2}{3}x=\dfrac{5}{7}-\dfrac{4}{5}=\dfrac{25-28}{35}=\dfrac{-3}{35}\)
=>\(x=-\dfrac{3}{35}:\dfrac{2}{3}=\dfrac{-3}{35}\cdot\dfrac{3}{2}=-\dfrac{9}{70}\)
c: \(\dfrac{1}{2}x+\dfrac{3}{5}x=-\dfrac{2}{3}\)
=>\(x\left(\dfrac{1}{2}+\dfrac{3}{5}\right)=-\dfrac{2}{3}\)
=>\(x\cdot\dfrac{5+6}{10}=\dfrac{-2}{3}\)
=>\(x\cdot\dfrac{11}{10}=-\dfrac{2}{3}\)
=>\(x=-\dfrac{2}{3}:\dfrac{11}{10}=-\dfrac{2}{3}\cdot\dfrac{10}{11}=\dfrac{-20}{33}\)
d: \(\dfrac{4}{7}\cdot x-x=-\dfrac{9}{14}\)
=>\(\dfrac{-3}{7}\cdot x=\dfrac{-9}{14}\)
=>\(\dfrac{3}{7}\cdot x=\dfrac{9}{14}\)
=>\(x=\dfrac{9}{14}:\dfrac{3}{7}=\dfrac{9}{14}\cdot\dfrac{7}{3}=\dfrac{3}{2}\)
4 tìm x :
a) x - 5/7 - 13/14 = 1
b) 3/5 + x + 11/5 = 11/3
a) x - 5/7 - 13/14 = 1
⇒ x - ( 5/7 + 13/14 ) = 1
x - 23/14 = 1
x = 1 + 23/14
x = 37/14
b)
⇒ 3/5 + x+ 6/5 = 11/3
x + 9/5 = 11/3
x = 11/3 - 9/5
x = 28/15
Tìm x, biết:
a, 11/13 - ( 5/42 -x ) = - ( 5/28 - 11/13 )
b, | x + 4/15 | - | - 3,75 | = -| -2,15 |
c, ( 0,25 - 30% x ) . 1/3 = 1/4 - 31/6
d, ( x - 1/2 ) : 1/3 + 5/7 = 68/7
a, 11/13 - ( 5/42 - x ) = - (5/28 - 11/13)
11/13 - (5/42 - x) = - 5/28 + 11/13
- (5/42 - x) + 5/28 = -11/13 + 11/13
- 5/42 + x + 5/28 = 0
- 5/42 + x = 0 - 5/28
- 5/42 + x = - 5/28
x = -5/28 +5/42
x = - 5/84
b, / x + 4/15 \ - / - 3,75 \ = - / - 2,15 \
./ x + 4/15 \ - 3,75 = - 2,15
/ x + 4/15 \ = -2,15 + 3,75
/ x + 4/15 \ = 1,6
x + 4 / 15 = 1,6 hoặc x+ 4/15 = - 1,6
x = 1,6 - 4/15 x = - 1,6 -4/15
x = 4/3 x = -28/15
Vậy x = 4/3 hoặc x = - 28/15
c, ( 0,25 - 30% x ) . 1/3 = 1/4 - 31/6
( 1/4 - 3/10 x ) . 1/3 = - 59/12
( 1/4 - 3/10 x ) = - 59/12 : 1/3
1/4 - 3/10 x = - 59/4
3/10 x = 1/4 + 59/4
3/10 x = 15
x = 15 : 3/10
x = 50
d, ( x - 1/2 ) : 1/3 + 5/7 = 68/7
( x - 1/2 ) : 1/3 = 68/7 - 5/7
( x - 1/2 ) : 1/3 = 63/7
( x - 1/2 ) = 63/7 . 1/3
x -1/2 = 3
x = 3 + 1/2
x = 7/2
Tìm x:
a) x + 30% x = -1,31
b) ( x - 1/2 ) : 1/3 + 5/7 = 9 5/7 (hỗn số)
c) 1/2x - 3/4 = 14/9 . 3/7
d) -5/6 - x = 7/12 + -1/3
e) x + 3/ -15 = 1/3
f) (4,5 - 2x) .( -1 4/7(hỗn số)) = 11/14
BẠN NÀO GIÚP MK MK SẼ TICK
a) x+30%x=-1.31
=> 100%x+30%x=-1.31
=>x.(100%+30%)=-1.31
=>x.13/10=-1.31=-1.31:13/10=-131/130
b) (x-1/2):1/3+5/7=9+5/7
=>(x-1/2).3+5/7=68/7
=>(x-1/2).3=68/7-5/7=9
=>x-1/2=9:3=3
=>x=3+1/2=3 1/2( hỗn số)
c) 1/2x-3/4=14/9.3/7
=>1/2x-3/4=2/3
=>1/2x=2/3+3/4=17/12
x=17/12:1/2=17/12.2=17/6
d) - 5/6 -x = 7/12+ -1/3
=>- 5/6 -x = 7/12+ -4/12=1/4
=> x = -5/6 -1/4=-13/12
e) x + 3/-15 = 1/3
=> x= 1/3 - -3/15 =1/3+3/15
=> x=5/15 + 3/15=8/15
f) (4,5 -2 x). (-1 4/7)=11/14
=> 4,5 -2x=11/14 : -3/7=11/14. -7/3=-11/6
=>-2x=-11/6-9/2= -11/6 -27/6 =-19/3
=>x= -19/3: -2x=19/6
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