Tìm x
3,8\(\div\)(x+1,05)=19/27
tìm x
3,8 : ( X - 1,05 ) = 19/9 : 1/3 ( phân số )
3,8 : (x- 1,05) = \(\frac{19}{9}:\frac{1}{3}\)
3,8 : ( x - 1,05) = \(\frac{19}{3}\)
x - 1,05 = \(3,8:\frac{19}{3}=\frac{3}{5}\)
x = \(\frac{3}{5}+1,05=\frac{33}{20}\)
25,7 - ( x + 1,05 ) = 3,8
25,7 - (x + 1,05) = 3,8
x + 1,05 = 25,7 - 3,8
x + 1,05 = 21,9
x = 21,9 - 1,05
x = 20,85
25,7 - (x + 1,05) = 3,8
x + 1,05 = 25,7 - 3,8
x + 1,05 = 21,9
x = 21,9 - 1,05
x = 20,85
Bài 1 . Tìm X
a) 7/15 < X/40 < 8/15 ( phân số )
b) X - 140 : 35 = 270
c) 180 - ( X - 45 ) : 2 = 120
d) ( X - 2 ) x 3 - 270 : 45 = 120
e) 3,8 : ( X - 1,05 ) = 19/9 : 1/3 ( phân số )
f) 2 - ( 43/8 + X - 168/24 ) : 38/3 = 0
[ 3,8 : ( x + 1,05 ) ] : 1/3 = 2 1/9
[ 3,8 : ( x + 1,05 ) ] : 1/3 = 2 1/9
19/5 : ( x + 1,05 ) = 21/9 x 1/3
19/5 : ( x + 1,05) = 7/9
x + 1,05 = 19/5 : 7/9
x + 21/20 = 171/35
x = 171/35 - 21/20
x = 228/49
[ 3,8 : ( x + 1,05 ) ] : 1/3 = 2 1/9
=> 3,8 : ( x+1,05) = 19/9 x 1/ 3 = 19/27
=> x + 1,05 = 3,8 : 19/27 = 5,4
=> x= 5,4-1,05 = 4,35
\(\left(3,8:\left(x+1,05\right)\right):\frac{1}{3}=\frac{21}{9}\)
\(=>3,8:\left(x+1,05\right)=\frac{7}{9}\)
\(=>x+1,05=\frac{171}{35}\)
\(=>x=\frac{537}{140}\)
Sai hết rồi nha @@@@
Tìm x biết: \(\left(\frac{2}{11\times13}+\frac{2}{13\times15}+...+\frac{2}{19\times21}\right)462-\left[0,04\div\left(x+1,05\right)\right]\div0,12=19\)
Ta có : \(\left(\frac{2}{11.13}+\frac{2}{13.15}+...+\frac{2}{19.21}\right)642-\left[0,04:\left(x+1,05\right)\right]:0,12=19\)
=> \(\left(\frac{1}{11}-\frac{1}{13}+\frac{1}{13}-\frac{1}{15}+...+\frac{1}{19}-\frac{1}{21}\right)642-0,04:\left(x+1,05\right):0,12=19\)
=>
(nãy bấm nhầm) tiếp nà :
=> \(\left(\frac{1}{11}-\frac{1}{21}\right)462-0,04:\left(x+1,05\right):0,12=19\)
=> \(\frac{10}{231}.462-0,04:\left(x+1,05\right):0,12=19\)
=> \(20-0,04:\left(x+1,05\right):0,12=19\)
=> 0,04 : (x + 1,05) : 0,12 = 1
=> 0,04 : (x + 1,05) = 0,12
=> \(x+1,05=\frac{1}{3}\)
=> \(x=\frac{1}{3}-1,05=...\)
\(\left(\frac{2}{11.13}+\frac{2}{13.15}+...+\frac{2}{19.21}\right)562-\left[0,04:\left(x+1,05\right)\right]:0,12=19\)
\(\Rightarrow2.\frac{1}{2}\left(\frac{1}{11}-\frac{1}{13}+\frac{1}{13}-\frac{1}{15}+...+\frac{1}{19}-\frac{1}{21}\right)462-\left[0,04:\left(x+1,05\right)\right]:0,12=19\)
\(\Rightarrow\left(\frac{1}{11}-\frac{1}{21}\right)462-\left[0,04:\left(x+1,05\right)\right]:0,12=19\)
\(\Rightarrow\frac{10}{231}.462-\left[0,04:\left(x+1,05\right)\right]:0,12=19\)
\(\Rightarrow20-\left[0,04:\left(x+1,05\right)\right]0,12=19\)
\(\Rightarrow\left[0,04:\left(x+1,05\right)\right]:0,12=20-19=1\)
\(\Rightarrow0,04:\left(x+1,05\right)=1.0,12=0,12\)
\(\Rightarrow x+1,05=0,04:0,12=\frac{1}{3}\)
\(\Rightarrow x=\frac{1}{3}-1,05=\frac{1}{3}-\frac{105}{100}=-\frac{43}{60}\)
(Làm vậy đúng không?)
Tìm x
[3,8:(x+1,05)]:1/3=2 và 1/9
cô mình bảo là đổi hết ra phân số
giúp mình nhé
2 và 1/9 là hỗn số nhé
[3,8 : (x + 1,05)] : \(\frac{1}{3}\)= 2\(\frac{1}{9}\)
\(\left[\frac{19}{5}:\left(x+\frac{21}{20}\right)\right]:\frac{1}{3}=\frac{19}{9}\)
\(\frac{19}{5}:\left(x+\frac{21}{20}\right)=\frac{19}{9}.\frac{1}{3}=\frac{19}{27}\)
\(x+\frac{21}{20}=\frac{19}{5}:\frac{19}{27}=\frac{27}{5}\)
\(x=\frac{27}{5}-\frac{21}{20}\)
\(x=\frac{87}{20}\)
3,8 :( x+1,05) =2 1/9x 1/3
3,8 : [ x+1,05 ] = 31/9 x1/3 3,8 : [ x + 1,05 ] = 31/27 3,8 : x = 31/27 - 1,05 3,8 : x =151/180 x= 151/180 x 3,8 x=1510/6840
(2/11x13 +2/13x15 +...+2/19x21)x426-(2,04:(x+1,05)):0,12=19
tìm x hộ mình nhé
2,4 x 10 = .......... 3,8 x 100 = .......... 4,86 x 1000 = .............
1,54 x 10 =........... 1,05 x 100= ......... 0,458 x 1000 = ............