Tìm x biết:
a) (15 × 19 – x – 0,15):0,25 = 15 : 0,25
b)\(2\frac{2}{3}-x=\frac{1}{3}\cdot\frac{6}{2}\)
Những câu hỏi liên quan
Bài 1 :Sắp xếp các phân số theo thứ tự từ bé đến lớn :
a) 5/6 ; 10/11 ; 15/16 ; 7/8
b) 15/14 ; 14/21 ; 5/6 ; 8/7 ; 51/42
Bài 2 : Tìm x , biết :
a) (15 x 19 - x - 0,15 ) : 0,25 = 15 : 0,25
b) 2 3/4 - x = 1/3 x 6/2
(15x 19 - x - 0,15 ) : 0,25 = 15 : 0,25
( 285 - x - 0,15) x 4 = 15 x 4
(285 -x - 0,15 ) x 4 = 60
285 - 0,15 - x = 60 : 4
285 - 0,15 -x = 15
284,85 - x = 15
x= 284,85 - 15
x= 269,85
Đúng 0
Bình luận (0)
Xem thêm câu trả lời
tìm x
a) ( 15 . 19 - x -0,15) : 0,25 = 15:0,25
b) 2012:x +23 = 526
c) x + 2/3 = 18 :9 -1
d) 5 .x - 1952 = 2500-1947
e ) x . 2011 - x = 2011 . 2009 + 2011
Tính
A) \(\frac{15}{34}+\frac{7}{21}+\frac{19}{34}-1\frac{15}{17}+\frac{2}{3}\)
B) \(\left(-2\right)^3\times\left(\frac{3}{4}-0,25\right):\left(2\frac{1}{4}-1\frac{1}{6}\right)\)
Tìm x
A) \(4\frac{1}{3}:\frac{\chi}{4}=6:0,3\)
B) \(\left(2^3:4\right)\times2^{\left(\chi+1\right)}=64\)
Tính:
b) \(\left(-2\right)^3.\left(\frac{3}{4}-0,25\right):\left(2\frac{1}{4}-1\frac{1}{6}\right)\)
\(=\left(-2\right)^3.\left(\frac{3}{4}-\frac{1}{4}\right):\left(\frac{9}{4}-\frac{7}{6}\right)\)
\(=\left(-8\right).\frac{1}{2}:\frac{13}{12}\)
\(=\left(-4\right):\frac{13}{12}\)
\(=-\frac{48}{13}.\)
Tìm x
a) \(4\frac{1}{3}:\frac{x}{4}=6:0,3\)
⇒ \(\frac{13}{3}:\frac{x}{4}=20\)
⇒ \(\frac{x}{4}=\frac{13}{3}:20\)
⇒ \(\frac{x}{4}=\frac{13}{60}\)
⇒ \(x.60=4.13\)
⇒ \(x.60=52\)
⇒ \(x=52:60\)
⇒ \(x=\frac{13}{15}\)
Vậy \(x=\frac{13}{15}.\)
b) \(\left(2^3:4\right).2^{x+1}=64\)
⇒ \(\left(8:4\right).2^{x+1}=64\)
⇒ \(2.2^{x+1}=64\)
⇒ \(2^{x+1}=64:2\)
⇒ \(2^{x+1}=32\)
⇒ \(2^{x+1}=2^5\)
⇒ \(x+1=5\)
⇒ \(x=5-1\)
⇒ \(x=4\)
Vậy \(x=4.\)
Chúc bạn học tốt!
Đúng 0
Bình luận (0)
Bài 1a) Tìm x, biết frac{2cdot x-4,36}{0,125} 0,25 * 42,9 - 11,7 * 0,25 + 0,25 * 0,8b) Tính nhanhNfrac{1}{1cdot5}+frac{1}{5cdot10}+frac{1}{10cdot15}+frac{1}{15cdot20}+...+frac{1}{2005cdot2010}Bài 2a) Tìm x, biết (x + 5,2) : 3,2 4,7 (dư 0,5).b) Tính nhanh:Afrac{4047991-2010cdot2009}{4050000-2011cdot2009}Bài 3a) Tìm x, biết 104,5 x X - 14,1 × X + 9,6 x X 25b) Tính nhanhTfrac{2009cdot2010+2000}{2011cdot2010-2020}
Đọc tiếp
Bài 1
a) Tìm x, biết
\(\frac{2\cdot x-4,36}{0,125}\)= 0,25 * 42,9 - 11,7 * 0,25 + 0,25 * 0,8
b) Tính nhanh
\(N=\frac{1}{1\cdot5}+\frac{1}{5\cdot10}+\frac{1}{10\cdot15}+\frac{1}{15\cdot20}+...+\frac{1}{2005\cdot2010}\)
Bài 2
a) Tìm x, biết (x + 5,2) : 3,2 = 4,7 (dư 0,5).
b) Tính nhanh:\(A=\frac{4047991-2010\cdot2009}{4050000-2011\cdot2009}\)
Bài 3
a) Tìm x, biết 104,5 x X - 14,1 × X + 9,6 x X = 25
b) Tính nhanh
\(T=\frac{2009\cdot2010+2000}{2011\cdot2010-2020}\)
\(\frac{2x-4,36}{0,125}=0,25.42,9-11,7.0,25+0,25.0,8\)
\(\Leftrightarrow\frac{2x-4,36}{0,125}=0,25.\left(42,9-11.7+0,8\right)\)
\(\Leftrightarrow\frac{2x-4,36}{0,125}=0,25.32\)
\(\Leftrightarrow\frac{2x-4,36}{0,125}=8\)
\(\Leftrightarrow2x-4,36=1\)
\(\Leftrightarrow2x=5,36\)
\(\Leftrightarrow x=2,68\)
b) \(N=\frac{1}{1.5}+\frac{1}{5.10}+\frac{1}{10.15}+\frac{1}{15.20}+...+\frac{1}{2005.2010}\)
\(\Leftrightarrow N=\frac{1}{5}\left(1-\frac{1}{5}+\frac{1}{5}-\frac{1}{10}+\frac{1}{10}-\frac{1}{15}+\frac{1}{15}-\frac{1}{20}+...+\frac{1}{2005}-\frac{1}{2010}\right)\)
\(\Leftrightarrow N=\frac{1}{5}\left(1-\frac{1}{2010}\right)\)
\(\Leftrightarrow N=\frac{1}{5}.\frac{2009}{2010}=\frac{2009}{10050}\)
Bài 1:
a)\(\frac{2\cdot x-4,36}{0,125}=0,25\cdot42,9-11,7\cdot0,25+0,25\cdot0,8\)
\(\frac{2\cdot x-4,36}{0,125}=0,25\cdot\left(42,9-11,7+0,8\right)\)
\(\frac{2\cdot x-4,36}{0,125}=0,25\cdot32\)
\(\frac{2\cdot x-4,36}{0,125}=8\)
\(2\cdot x-4,36=8\cdot0,125\)
\(2\cdot x-4,36=1\)
\(2\cdot x=1+4,36\)
\(2\cdot x=5,36\)
\(x=\frac{5,36}{2}=2,68\)
b) \(N=\frac{1}{1\cdot5}+\frac{1}{5\cdot10}+\frac{1}{10\cdot15}+\frac{1}{15\cdot20}+...+\frac{1}{2005\cdot2010}\)
\(4N=\frac{4}{1\cdot5}+\frac{4}{5\cdot10}+\frac{4}{10\cdot15}+\frac{4}{15\cdot20}+...+\frac{4}{2005\cdot2010}\)
\(4N=1-\frac{1}{5}+\frac{1}{5}-\frac{1}{10}+\frac{1}{10}-\frac{1}{15}+\frac{1}{15}-\frac{1}{20}+...+\frac{1}{2005}-\frac{1}{2010}\)
\(4N=1-\frac{1}{2010}=\frac{2009}{2010}\)
\(N=\frac{2009}{2010}\div4=\frac{2009}{8040}\)
Bài 2:
a) ( x + 5,2 ) : 3,2 = 4,7 ( dư 0,5 )
\(x+5,2=4,7\cdot3,2+0,5\)
\(x+5,2=15,54\)
\(x=15,54-5,2=10,34\)
b)\(A=\frac{4047991-2010\cdot2009}{4050000-2011\cdot2009}\)
\(A=\frac{4047991-2010\cdot2009}{4050000-2009-2010\cdot2009}\)
\(A=\frac{4047991-2010\cdot2009}{4047991-2010\cdot2009}=1\)
Bài 3:
a) \(104,5\cdot x-14,1\cdot x+9,6\cdot x=25\)
\(x\cdot\left(104,5-14,1+9,6\right)=25\)
\(x\cdot100=25\)
\(x=\frac{25}{100}=\frac{1}{4}=0,25\)
b) \(T=\frac{2009\cdot2010+2000}{2011\cdot2010-2020}\)
\(T=\frac{2009\cdot2010+2000}{2009\cdot2010+4020-2020}\)
\(T=\frac{2009\cdot2010+2000}{2009\cdot2010+2000}=1\)
Tìm x, biết:
a)\(x + \left( { - \frac{1}{5}} \right) = \frac{{ - 4}}{{15}}\);
b)\(3,7 - x = \frac{7}{{10}};\)
c)\(x.\frac{3}{2} = 2,4\);
d)\(3,2:x = - \frac{6}{{11}}\).
a)
\(\begin{array}{l}x + \left( { - \frac{1}{5}} \right) = \frac{{ - 4}}{{15}}\\x = \frac{{ - 4}}{{15}} + \frac{1}{5}\\x = \frac{{ - 4}}{{15}} + \frac{3}{{15}}\\x = \frac{{ - 1}}{{15}}\end{array}\)
Vậy \(x = \frac{{ - 1}}{{15}}\).
b)
\(\begin{array}{l}3,7 - x = \frac{7}{{10}}\\x = 3,7 - \frac{7}{{10}}\\x = \frac{{37}}{{10}} - \frac{7}{{10}}\\x=\frac{30}{10}\\x = 3\end{array}\)
Vậy \(x = 3\).
c)
\(\begin{array}{l}x.\frac{3}{2} = 2,4\\x.\frac{3}{2} = \frac{{12}}{5}\\x = \frac{{12}}{5}:\frac{3}{2}\\x = \frac{{12}}{5}.\frac{2}{3}\\x = \frac{8}{5}\end{array}\)
Vậy \(x = \frac{8}{5}\)
d)
\(\begin{array}{l}3,2:x = - \frac{6}{{11}}\\\frac{{16}}{5}:x = - \frac{6}{{11}}\\x = \frac{{16}}{5}:\left( { - \frac{6}{{11}}} \right)\\x = \frac{{16}}{5}.\frac{{ - 11}}{6}\\x = \frac{{ - 88}}{{15}}\end{array}\)
Vậy \(x = \frac{{ - 88}}{{15}}\).
Đúng 0
Bình luận (0)
a , 3 phần 4 : x phần 6 = 0,75
b , [ 15 x 19 - x - 0,15 ] : 0,25 = 15 : 0,25
c , [ x + 1,1 ] + [ x + 2,2 ] + [ x + 3,3 ] + ... + [ x + 13,2 ] = 119 , 4
Câu 1: Thực hiện phép tính bằng cách hợp lífrac{15}{35}+frac{7}{21}+frac{19}{34}-1frac{15}{17}+frac{2}{3}left(-2right)^3.left(frac{3}{4}-0,25right):left(2frac{1}{4}-1frac{1}{6}right)16frac{2}{7}:left(-frac{3}{5}right)+28frac{2}{7}:left(-frac{3}{5}right)Câu 2: Tìm x biết2.x-frac{5}{4}frac{20}{15}1,5:0,3x:-15|2x-1|2Câu 3: Thực hiện phép tính hợp lífrac{11}{12}.frac{15}{33}+frac{11}{12}.frac{2}{22}3/3frac{1}{8}.11frac{17}{19}-3frac{1}{8}.13frac{17}{19}28frac{2}{7}:left(-frac{3}{5}right)+16frac{2}{7...
Đọc tiếp
Câu 1: Thực hiện phép tính bằng cách hợp lí
\(\frac{15}{35}+\frac{7}{21}+\frac{19}{34}-1\frac{15}{17}+\frac{2}{3}\)
\(\left(-2\right)^3.\left(\frac{3}{4}-0,25\right):\left(2\frac{1}{4}-1\frac{1}{6}\right)\)
\(16\frac{2}{7}:\left(-\frac{3}{5}\right)+28\frac{2}{7}:\left(-\frac{3}{5}\right)\)
Câu 2: Tìm x biết
\(2.x-\frac{5}{4}=\frac{20}{15}\)
\(1,5:0,3=x:-15\)
\(|2x-1|=2\)
Câu 3: Thực hiện phép tính hợp lí
\(\frac{11}{12}.\frac{15}{33}+\frac{11}{12}.\frac{2}{22}\)
\(3/3\frac{1}{8}.11\frac{17}{19}-3\frac{1}{8}.13\frac{17}{19}\)
\(28\frac{2}{7}:\left(-\frac{3}{5}\right)+16\frac{2}{7}:\left(-\frac{3}{5}\right)\)
Thực hiện phép tính :
a/ \(\left(\frac{4}{15}+\frac{7}{12}-\frac{19}{20}\right)\cdot2,5+0,25\)
b/ \(25\cdot\left(\frac{-1}{5}\right)^3+\frac{1}{5}-2\left(\frac{-1}{2}\right)^2-\frac{1}{2}\)
Tìm x, biết :
a) \(x\cdot\frac{1}{2}+x\cdot\frac{1}{4}+x\cdot\frac{1}{8}=\frac{21}{24}\)
b) (x+4)+(x+9)+(x+14)+...+(x+44)+(x+49)=1430
c) x* 0,25-0,5=1
Chứng minh rằng (9^2n+1994^93)chia heets cho 5
Đúng 0
Bình luận (0)
a) \(x\cdot\frac{1}{2}+x\cdot\frac{1}{4}+x\cdot\frac{1}{8}=\frac{21}{24}\)
\(x\cdot\left(\frac{1}{2}+\frac{1}{4}+\frac{1}{8}\right)=\frac{7}{8}\)
\(x\cdot\frac{7}{8}=\frac{7}{8}\)
\(\Rightarrow x=\frac{7}{8}\div\frac{7}{8}=1\)
b) \(\left(x+4\right)+\left(x+9\right)+\left(x+14\right)+.....+\left(x+44\right)+\left(x+49\right)=1430\)
\(\left(x+x+x+....+x+x\right)+\left(4+9+14+...+44+49\right)=1430\)
\(10x+265=1430\)
\(10x=1430-265\)
\(10x=1165\)
\(\Rightarrow x=\frac{1165}{10}=116,5\)
c) \(x\cdot0,25-0,5=1\)
\(x\cdot0,25=1+0,5\)
\(x\cdot0,25=1,5\)
\(\Rightarrow x=1,5\div0,25=6\)
Đúng 0
Bình luận (0)