[ 25 x 24 - X] : 0.25 = 100 : 1/4
(15 x 24 - X ) :0.25 =100 : 41
Tìm X
(15.24 - x) : 0,25 = 100 : 41
=> (360 - x) . 4 = 100/41
=> 360 - x = 100/41 : 4
=> 360 - x = 25/41
=> x = 360 - 25/41
=> x = \(359\frac{16}{41}\)
đề của một số bạn là \(\frac{1}{4}\)chứ ko phải 41 đâu bạn
tìm x
a, X:0.25+X x 11=24
b, X x 8.01-X: 100=38
a, X:0.25+X x 11=24
X x 4 + X x 11 = 24
X x (11 + 4) = 24
X x 15 = 24
X = 24 : 15
X = 1,6
b, X x 8.01-X: 100=38
X x 8,01 - X x 0,01 = 38
X x (8,01 - 0,01) = 38
X x 8 = 38
X = 38 : 8
X = 4,75`
a, X:0.25+X x 11=24
X x 4 + X x 11 = 24
X x (11 + 4) = 24
X x 15 = 24
X = 24 : 15
X = 1,6
b, X x 8.01-X: 100=38
X x 8,01 - X x 0,01 = 38
X x (8,01 - 0,01) = 38
X x 8 = 38
X = 38 : 8
X = 4,75
a) X : 0,25 + X x 11 = 24
X x 4 + X x 11 = 24
X x ( 11 + 4 ) = 24
X x 15 = 24
X = 24 : 15
X = 1,6
b, X x 8 , 01 - X : 100 = 38
X x 8,01 - X x 0,01 = 38
X x ( 8,01 - 0,01 ) = 38
X x 8 = 38
X = 38 : 8
X = 4,75
tinhs giá trị biểu thức: ( 75% + 0.65 + 1/4 + 35%) x ( 1/4 x 2 + 25% x 3 + 0.25 x 5)
\(=\left(\frac{75}{100}+\frac{65}{100}+\frac{1}{4}+\frac{35}{100}\right)\left(\frac{1}{4}.2+\frac{25}{100}.3+\frac{25}{100}.5\right)\)
\(=\left(\frac{3}{4}+\frac{13}{20}+\frac{1}{4}+\frac{7}{20}\right)\left(\frac{2}{4}+\frac{3}{4}+\frac{5}{4}\right)\)
\(=\left(1+1\right).\frac{10}{4}\)
\(=2.\frac{5}{2}\)
\(=5\)
Tính bằng cách hợp lí : 0.25 + 25% x 55 + 1/4 x 45 - 2/8
\(0,25+25\%\times55+\dfrac{1}{4}\times45-\dfrac{2}{8}\)
\(=\dfrac{1}{4}+\dfrac{1}{4}\times55+\dfrac{1}{4}\times45-\dfrac{1}{4}\)
\(=\dfrac{1}{4}\times\left(1+55+45-1\right)\)
\(=\dfrac{1}{4}\times100\)
\(=25\)
\(0,25+25\%\times55+\dfrac{1}{4}\times45-\dfrac{2}{8}\)
\(=\dfrac{1}{4}+\dfrac{1}{4}\times55+\dfrac{1}{4}\times45-\dfrac{1}{4}\)
\(=\dfrac{1}{4}\times1+\dfrac{1}{4}\times55+\dfrac{1}{4}\times45-\dfrac{1}{4}\times1\)
\(=\dfrac{1}{4}+\left(1+55+45-1\right)\)
\(=\dfrac{1}{4}\times100\)
\(=0,25\times100\)
\(=25\)
\(#:)\)
tinhs giá trị biểu thức:
( 75% + 0.65 + 1/4 + 35%) x ( 1/4 x 2 + 25% x 3 + 0.25 x 5)
(1/2+0.25+1/4)nhan ( 1/8+1/2+1/8+25/100) nhan (0.75+1/2)+0.50+1/4+0.55+45/100)
1/ (\(\left(-\dfrac{2}{3}\right)\)\(^2\) x \(\dfrac{-9}{8}\) - 25% x \(\dfrac{-16}{5}\)
2/ -1\(\dfrac{2}{5}\) x 75% + \(\dfrac{-7}{5}\) x 25%
3/ -2\(\dfrac{3}{7}\) x (-125%) + \(\dfrac{-17}{7}\) x 25%
4/ (-2)\(^3\) x (\(\dfrac{3}{4}\) x 0.25) : (2\(\dfrac{1}{4}\) - 1\(\dfrac{1}{6}\))
1) Ta có: \(\left(-\dfrac{2}{3}\right)^2\cdot\dfrac{-9}{8}-25\%\cdot\dfrac{-16}{5}\)
\(=\dfrac{4}{9}\cdot\dfrac{-9}{8}-\dfrac{1}{4}\cdot\dfrac{-16}{5}\)
\(=\dfrac{-1}{2}+\dfrac{4}{5}\)
\(=\dfrac{-5}{10}+\dfrac{8}{10}=\dfrac{3}{10}\)
2) Ta có: \(-1\dfrac{2}{5}\cdot75\%+\dfrac{-7}{5}\cdot25\%\)
\(=\dfrac{-7}{5}\cdot\dfrac{3}{4}+\dfrac{-7}{5}\cdot\dfrac{1}{4}\)
\(=\dfrac{-7}{5}\left(\dfrac{3}{4}+\dfrac{1}{4}\right)=-\dfrac{7}{5}\)
3) Ta có: \(-2\dfrac{3}{7}\cdot\left(-125\%\right)+\dfrac{-17}{7}\cdot25\%\)
\(=\dfrac{-17}{7}\cdot\dfrac{-5}{4}+\dfrac{-17}{7}\cdot\dfrac{1}{4}\)
\(=\dfrac{-17}{7}\cdot\left(\dfrac{-5}{4}+\dfrac{1}{4}\right)\)
\(=\dfrac{17}{7}\)
4) Ta có: \(\left(-2\right)^3\cdot\left(\dfrac{3}{4}\cdot0.25\right):\left(2\dfrac{1}{4}-1\dfrac{1}{6}\right)\)
\(=\left(-8\right)\cdot\left(\dfrac{3}{4}\cdot\dfrac{1}{4}\right):\left(\dfrac{9}{4}-\dfrac{7}{6}\right)\)
\(=\left(-8\right)\cdot\dfrac{3}{16}:\dfrac{54-28}{24}\)
\(=\dfrac{-3}{2}\cdot\dfrac{24}{26}\)
\(=\dfrac{-72}{52}=\dfrac{-18}{13}\)
( 1/24 x 25 + 1/25 x 26 + ... + 1/29 x 30 ) x 150 + 103/100 [ 103/100 x ( X - 1 ) ] = 22