\(7.5x:\left(9-6\frac{13}{21}\right)=2\frac{13}{25}\)
.tìm x:
\(7,5x:\left(9-6\frac{13}{21}\right)=2\frac{13}{25}\)
\(7,5x:\left(9-\frac{139}{21}\right)=\frac{63}{25}\)
\(7,5x:\left(\frac{189}{21}-\frac{139}{21}\right)=\frac{63}{25}\)
\(7,5x:\left(\frac{50}{21}\right)=\frac{63}{25}\)
\(7,5x=\frac{63}{25}.\frac{50}{21}\)
\(7,5x=6\)
\(x=6:7,5\)
\(x=\frac{4}{5}\)
vậy \(x=\frac{4}{5}\)
k mk nha vì mk đang âm điểm
tìm x biết:
a,\(7,5x:\left(9-6\frac{13}{21}\right)=2\frac{13}{25}\)
b,\(\frac{\left(1,16-x\right)\cdot5,25}{\left(10\frac{5}{9}-7\frac{1}{4}\right)\cdot2\frac{2}{17}}\)=75%
7,5x:\(\left[9-6\frac{13}{21}\right]=2\frac{13}{25}\)
\(7,5x:\left[9-6\frac{13}{21}\right]=2\frac{13}{25}\)
\(\Leftrightarrow7,5x:\left[9-\frac{139}{21}\right]=\frac{63}{25}\)
\(\Leftrightarrow7,5x:\frac{50}{21}=\frac{63}{25}\)
\(\Leftrightarrow7,5x=\frac{63}{25}.\frac{50}{21}\)
\(\Leftrightarrow7,5x=6\)
\(\Leftrightarrow x=6:7,5\)
\(\Leftrightarrow x=\frac{4}{5}=0,8\)
(Chúc bạn học tốt và tíck cho mìk vs nha!)
1, tìm x biết:
a, 7.5x : ( 9 - 6\(\frac{13}{21}\) = 2\(\frac{13}{25}\)
b, ( 1.16 - x ) . 5.25 / ( 10\(\frac{5}{9}\)- 7\(\frac{1}{4}\)) . 2\(\frac{2}{17}\)= 75%
Cường song joong ki tra loi chi tiet giúp mk với. Cảm ơn nhiu con cau tra loi cua bn mk se ...tick cho!
Tính:
a)\(A = \frac{5}{{11}}.\left( {\frac{{ - 3}}{{23}}} \right).\frac{{11}}{5}.\left( { - 4,6} \right);\) b) \(B = \left( {\frac{{ - 7}}{9}} \right).\frac{{13}}{{25}} - \frac{{13}}{{25}}.\frac{2}{9}\)
a)
\(\begin{array}{l}A = \frac{5}{{11}}.\left( {\frac{{ - 3}}{{23}}} \right).\frac{{11}}{5}.\left( { - 4,6} \right)\\A = \frac{5}{{11}}.\left( {\frac{{ - 3}}{{23}}} \right).\frac{{11}}{5}.\frac{{ - 23}}{5}\\A = \frac{{5.\left( { - 3} \right).11.\left( { - 23} \right)}}{{11.23.5.5}}\\A = \frac{3}{5}\end{array}\)
b)
\(\begin{array}{l}B = \left( {\frac{{ - 7}}{9}} \right).\frac{{13}}{{25}} - \frac{{13}}{{25}}.\frac{2}{9}\\B = \frac{{13}}{{25}}.\left( {\frac{{ - 7}}{9} - \frac{2}{9}} \right)\\B = \frac{{13}}{{25}}.(-1)\\B = \frac{{-13}}{{25}}.\end{array}\)
Tìm x biết: a) 7,5x : \(\left(9-6\frac{13}{21}\right)\)= \(2\frac{14}{25}\)
7,5x:\(\frac{50}{21}\)=\(\frac{64}{25}\)
7,5x = \(\frac{64}{25}.\frac{50}{21}\)
7,5x = \(\frac{128}{21}\)
x = \(\frac{128}{21}:7,5\)
x = \(\frac{256}{315}\)
tính hợp lí
\(\left[\left(25\frac{12}{67}+9\frac{13}{41}\right)_{ }-\left(8\frac{12}{67}-3\frac{28}{41}\right)\right]X\frac{21}{-13}\)
làm ơn giúp mk nhanh nhé mai mk đi học rồi
\(=\left(25+\dfrac{12}{67}+9+\dfrac{13}{41}-8-\dfrac{12}{67}+3+\dfrac{28}{41}\right)\cdot\dfrac{-21}{13}\)
\(=\left(25+9-8+3+1\right)\cdot\dfrac{-21}{13}=\dfrac{-630}{13}\)
Rút gọn
1.\(\left(\frac{2}{45}-\frac{4}{13}-\frac{1}{3}\right):\left(\frac{3}{13}-\frac{4}{15}+\frac{2}{13}\right)\)
2.\(\frac{0,8:\left(\frac{4}{5}.1,25\right)}{0,64-\frac{1}{25}}+\frac{\left(1,08-\frac{2}{15}\right):\frac{4}{7}}{\left(6\frac{5}{9}-3\frac{1}{4}\right)2\frac{2}{17}}\)
3.\(\frac{0,4-\frac{2}{9}+\frac{2}{11}}{1,4-\frac{7}{9}+\frac{7}{11}}-\frac{\frac{1}{3}-0,25+\frac{1}{5}}{1\frac{1}{6}-0,875+0,7}\)
2: \(=\dfrac{0.8}{\dfrac{16}{25}-\dfrac{1}{25}}+\dfrac{\dfrac{71}{75}\cdot\dfrac{7}{4}}{\dfrac{119}{36}\cdot\dfrac{36}{17}}\)
\(=\dfrac{4}{5}\cdot\dfrac{5}{3}+\dfrac{71}{300}=\dfrac{471}{300}=\dfrac{157}{100}\)
3: \(=\dfrac{\dfrac{2}{5}-\dfrac{2}{9}+\dfrac{2}{11}}{\dfrac{7}{5}-\dfrac{7}{9}+\dfrac{7}{11}}-\dfrac{\dfrac{2}{6}-\dfrac{2}{8}+\dfrac{2}{10}}{\dfrac{7}{6}-\dfrac{7}{8}+\dfrac{7}{10}}\)
=2/7-2/7=0
Tính
a) \(\left(\frac{-13}{25}.\right).\frac{5}{32}.\frac{25}{-13}.\left(-64\right)\)
b) \(\frac{4}{9}:\left(\frac{-1}{7}\right)+6\frac{5}{9}:\left(-\frac{1}{7}\right)\)