Tìm x biết: a) (3/4.x-0,54) : (-2/9) =0,48 - 3/4
Tìm x biết:
a) (3/4.x-0,54) : (-2/9) =0,48 - 3/4
\(\left(\frac{3}{4}\cdot X-0.54\right):\left(-\frac{2}{9}\right)=0.48-\frac{3}{4}\)
\(\left(\frac{3}{4}.X-0.54\right):\left(-\frac{2}{9}\right)=\frac{-27}{100}\)
\(\left(\frac{3}{4}.X-0.54\right)=\frac{-27}{100}.\frac{-2}{9}\)
\(\left(\frac{3}{4}.X-0.54\right)=\frac{3}{50}\)
\(\frac{3}{4}.X=\frac{3}{50}+0.54\)
\(\frac{3}{4}.X=\frac{3}{50}+\frac{27}{50}\)
\(\frac{3}{4}.X=\frac{3}{5}\)
X= \(\frac{3}{5}:\frac{3}{4}\)
X= \(\frac{3}{5}.\frac{4}{3}\)
X=\(\frac{4}{5}\)
(\(\frac{3}{4}\) * x - 0,54 ) : \(\frac{2}{9}\)=\(\frac{3}{4}\)- 0,48
tỉm x
\(\left(\frac{3}{4}\times x-0,54\right):\frac{2}{9}=\frac{3}{4}-0,48\)
\(\left(\frac{3}{4}\times x-0,54\right):\frac{2}{9}=0,27\)
\(\left(\frac{3}{4}\times x-0,54\right)=0,27\times\frac{2}{9}\)
\(\left(\frac{3}{4}\times x-0,54\right)=0,06\)
\(\frac{3}{4}\times x=0,06+0,54\)
\(\frac{3}{4}\times x=0,6\)
\(x=0,6:\frac{3}{4}\)
\(x=0,8\)
(3/4 *x -0.54):2/9 = 3/4- 12/25
(3/4 *x- 27/50) :2/9 =27/100
3/4*x- 27/50 = 27/100* 2/9
3/4*x-27/50 = 3/50
3/4*x = 3/50+ 27/50
3/4*x =3/5
x= 3/5:3/4= 4/5
Tìm x:
(3/4*x-0,54)*4/9+8/75=4/15
( 3/4 . x - 0,54 ) . 4/9 + 8/75 = 4/15
( 3/4 . x - 0,54 ) . 4/9 = 4/15 - 8/75
( 3/4 . x - 0,54 ) . 4/9 = 4/25
3/4 . x - 0,54 = 4/25 : 4/9
3/4 . x - 0,54 = 9/25
3/4 . x = 9/25 + 0,54
3/4 . x = 9/10
x = 3/4 : 9/10
x = 5/6
\(\left(\frac{3}{4}x-0,54\right)\frac{4}{9}+\frac{8}{75}=\frac{4}{15}\)
\(\left(\frac{3}{4}x-\frac{27}{50}\right)\frac{4}{9}=\frac{4}{15}-\frac{8}{15}=\frac{-4}{15}\)
\(\frac{3}{4}x-\frac{27}{50}=\frac{-4}{15}:\frac{4}{9}=\frac{-3}{5}\)
\(\frac{3}{4}x=\frac{-3}{5}+\frac{27}{50}=\frac{-3}{50}\)
\(x=\frac{-3}{50}:\frac{3}{4}\)
\(x=\frac{-2}{25}\)
1. tìm x
a, 2x - \(\dfrac{1}{2}\) : \(\dfrac{3}{4}\) = \(\dfrac{12}{9}\)
b, x\(^2\) - 2 = 0
2. Cho
A = \(\dfrac{1,11+0,19-13.2}{2,06+0,54}\) - \(\left(\dfrac{1}{2}+\dfrac{1}{4}\right)\) : 2
B = \(\left(5\dfrac{7}{8}-2\dfrac{1}{4}-0,5\right)\) : \(2\dfrac{23}{26}\)
a, Rút gọn A, B
b, Tìm x ϵ Z để A < x < B
a)
=\(2x-\dfrac{1}{2}=\dfrac{12}{9}\cdot\dfrac{3}{4}=1\)
=\(2x=1+\dfrac{1}{2}=1.5\)
=\(x=1.5:2=0.75\)
b)
=\(x^2=0+2=2\)
TH1:\(x=2\)
TH2:\(x=-2\)
Bài 1:
a: \(2x-\dfrac{1}{2}:\dfrac{3}{4}=\dfrac{12}{9}\)
=>\(2x-\dfrac{1}{2}\cdot\dfrac{4}{3}=\dfrac{4}{3}\)
=>\(2x=\dfrac{4}{3}+\dfrac{2}{3}=\dfrac{6}{3}=2\)
=>x=2/2=1
b: \(x^2-2=0\)
=>\(x^2=2\)
=>\(\left[{}\begin{matrix}x=\sqrt{2}\\x=-\sqrt{2}\end{matrix}\right.\)
Bài 2:
a: \(A=\dfrac{1,11+0,19-13\cdot2}{2,06+0,54}-\left(\dfrac{1}{2}+\dfrac{1}{4}\right):2\)
\(=\dfrac{1,3-26}{2,6}-\dfrac{3}{4}:2\)
\(=-9,5-\dfrac{3}{8}=-\dfrac{79}{8}\)
\(B=\left(5\dfrac{7}{8}-2\dfrac{1}{4}-0,5\right):\left(2\dfrac{23}{26}\right)\)
\(=\left(5+\dfrac{7}{8}-2-\dfrac{1}{4}-\dfrac{1}{2}\right):\dfrac{75}{26}\)
\(=\left(3+\dfrac{1}{8}\right)\cdot\dfrac{26}{75}=\dfrac{25}{8}\cdot\dfrac{26}{75}=\dfrac{13}{12}\)
b: A<x<B
=>\(-\dfrac{79}{8}< x< \dfrac{13}{12}\)
mà \(x\in Z\)
nên \(x\in\left\{-9;-8;...;0;1\right\}\)
tìm x biết :
a)x x 7/9=2/3 +2 và 1/2
b)5/7 + x :9/4=4/3
a) x × 7/9 = 2/3 + 2 1/2
x × 7/9 = 2/3 + 5/2
x × 7/9 = 19/6
x = 19/6 : 7/9
x = 57/14
b) 5/7 + x : 9/4 = 4/3
x : 9/4 = 4/3 - 5/7
x : 9/4 = 13/21
x = 13/21 × 9/4
x = 39/28
Một tốp thợ có 120 người dự địnhnlamf trong 50 ngày . Khi bắt đầu làm có một số người đến làm thêm nên làm xong công việc đó trong 30 ngày . Hỏi có bao nhiêu người đến thêm?
bài 1:Tìm x biết
a,X x 3/4 = 9/14 b,x : 5/9 = 3/10
bài 2:Tính
a, 3/10 + 2/5 : 4/15 b, 4/7 x 3 + 2/3 x 2
Giúp mình với nhé
Bài 1:
a) \(x.\dfrac{3}{4}=\dfrac{9}{14}\)
\(\Rightarrow x=\dfrac{9}{14}:\dfrac{3}{4}\)
\(\Rightarrow x=\dfrac{6}{7}\)
b) \(x:\dfrac{5}{9}=\dfrac{3}{10}\)
\(\Rightarrow x=\dfrac{3}{10}.\dfrac{5}{9}\)
\(\Rightarrow x=\dfrac{1}{6}\)
Bài 2:
a) \(\dfrac{3}{10}+\dfrac{2}{5}:\dfrac{4}{15}=\dfrac{3}{10}+\dfrac{3}{2}=\dfrac{9}{5}\)
b) \(\dfrac{4}{7}.3+\dfrac{2}{3}.2=\dfrac{12}{7}+\dfrac{4}{3}=\dfrac{64}{21}\)
Bài 1 : Tìm x, biết:
a) \(\left(\frac{1}{5}-\frac{3}{4}\right)x-1,52=-0,48\)
b,I x - 2 I - 1,5x = \(\frac{3}{4}+\frac{5}{4}x\)
c, \(\frac{5x}{0,75}=x:8\)
d, \(\frac{-6}{3x-2}=\frac{4}{x-1}\)
Giúp mik vs mai mik thi rùi!!!
tìm X biết :
a.2/3 : 5/7 : x/9 = 2/7 : 3/5 :10/9
b.3/5 : 7/x : 3/4 = 12/105
c.x : 1/2 = 2/3 x 4/5 x 3/4 x 15/8
a, \(\frac{2}{3}:\frac{5}{7}:\frac{x}{9}=\frac{2}{7}:\frac{3}{5}:\frac{10}{9}\Leftrightarrow\frac{2\times7\times9}{3\times5\times x}=\frac{2\times5\times9}{7\times3\times10}\Leftrightarrow\frac{42}{5\times x}=\frac{3}{7}\Leftrightarrow294=15\times x\Leftrightarrow x=19,6\)
Các phần sau tương tự.
Dùng phương pháp nhân chéo và kiểm tra trình độ tính toán, khả năng rút gọn.
Thay kết quả vào x để kiểm tra lại bài.
A=0,48 x 700 - 2,4 x 45 x 2
4,5 +3,5+2,5+1,5+0,5-4-3-2-1