Tìm x là số tự nhiên
a)\(1< \frac{11}{x}< 2\) b) \(\frac{15}{26}+\frac{x}{16}=\frac{46}{52}\)
Tìm x là số tự nhiên biết :
a) \(\frac{x}{17}=\frac{60}{204}\) b) \(\frac{6+x}{33}=\frac{7}{11}\) c) \(\frac{12+x}{43-x}=\frac{2}{3}\)
d)\(\frac{x}{5}< \frac{3}{7}\) e) \(1< \frac{11}{x}< 2\) g) \(\frac{15}{26}+\frac{x}{16}=\frac{46}{52}\)
HELP ME !
a)\(\frac{x}{17}=\frac{60}{204}=\frac{5}{17}\Rightarrow x=5\)
b)\(\frac{6+x}{33}=\frac{7}{11}\Rightarrow11\left(6+x\right)=7.33\Rightarrow11.6+11x=231\Rightarrow66+11x=231\)
\(\Rightarrow11x=231-66\Rightarrow11x=165\Rightarrow x=\frac{165}{11}=15\)
c)\(\frac{12+x}{43-x}=\frac{2}{3}\Rightarrow2\left(43-x\right)=3\left(12+x\right)\Rightarrow2.43-2x=3.12+3x\)
\(86-2x=36+3x\Rightarrow86-36=3x+2x\Rightarrow50=5x\Rightarrow x=\frac{50}{5}=10\)
Tìm x là số tự nhiên
A.\(\frac{6+x}{33}=\frac{7}{11}\)
B.\(\frac{15}{26}+\frac{x}{13}=\frac{46}{52}\)
C\(\frac{121}{27}X\frac{54}{11}< x< \frac{100}{21}:\frac{25}{126}\)
D.\(1< \frac{11}{x}< 12\)
a) X = 15
b) X = 4
c ) X= 23
d) X= 11
( Chỉ là ý kiến riêng thôi nhé, nhận gạch đá )
a) \(\frac{6+x}{33}=\frac{7}{11}\)
=> (6 + x). 11 = 33.7
=> 66 + 11x = 231
=> 11x = 231 - 66
=> 11x = 165
=> x = 165 : 11
=> x = 15
b) 15/26 + x/13 = 46/52
=> x/13 = 23/26 - 15/26
=> x/13 = 4/13
=> x = 4
c) 121/27 x 54/11 < x < 100/21 : 25/126
=> 22 < x < 24
=> x = 23 (vì x là số tự nhiên)
d) 1 < 11/x < 12
=> 11/x \(\in\){2; 3; 4 ; ...; 11}
=> x \(\in\) {11/2; 11/3; ...; 1}
Vì x là số tự nhiên => x = 1
Tìm x:
\(\frac{15}{26}\)+ \(\frac{x}{16}\)= \(\frac{46}{52}\)
Ai nhanh mk sẽ tik
\(\frac{46}{52}-\frac{15}{26}=\frac{46}{52}-\frac{30}{52}=\frac{16}{52}=\frac{4}{13}\)
\(\frac{15}{26}+\frac{x}{16}=\frac{46}{52}\)
\(\Leftrightarrow\frac{15}{26}+\frac{x}{16}=\frac{23}{26}\)
\(\Leftrightarrow\frac{x}{16}=\frac{23}{26}-\frac{15}{26}\)
\(\Leftrightarrow\frac{x}{16}=\frac{8}{26}=\frac{4}{13}\)
\(\Rightarrow13x=16\times4\)
\(\Rightarrow x=\frac{64}{13}\)
Bn phải ghi rõ x bằng bao nhiêu mk mới đc
\(\frac{15}{26}\)+\(\frac{x}{16}\)= \(\frac{46}{52}\)
\(\frac{15}{26}+\frac{x}{16}=\frac{46}{52}\)
\(\frac{x}{16}=\frac{46}{52}-\frac{15}{26}\)
\(\frac{x}{16}=\frac{4}{13}\)
\(< =>\frac{x}{208}=\frac{64}{208}=\frac{4}{13}\)
\(x=4\)
\(\frac{15}{26}+\frac{x}{16}=\frac{46}{52}\)
\(\Rightarrow\frac{15}{26}+\frac{x}{16}=\frac{23}{26}\)
\(\Rightarrow\frac{x}{16}=\frac{23}{26}-\frac{15}{26}\)
\(\Rightarrow\frac{x}{16}=\frac{4}{13}\)
\(\Rightarrow13x=4.16\)
\(\Rightarrow13x=64\)
\(\Rightarrow x=64:13\)
\(\Rightarrow x=\frac{64}{13}\)
Vậy x = \(\frac{64}{13}\)
_Chúc bạn học tốt_
Tìm số nguyên x
a) \(\frac{1}{3}+\frac{-2}{5}+\frac{1}{6}+\frac{-1}{5}\le x< \frac{-3}{4}+\frac{2}{7}+\frac{-1}{4}+\frac{3}{5}+\frac{5}{7}\)
b)\(\frac{5}{17}+\frac{-9}{4}+\frac{-26}{31}+\frac{12}{17}+\frac{-11}{31}< \frac{x}{9}\le\frac{-3}{7}+\frac{7}{15}+\frac{4}{-7}+\frac{8}{15}\)
\(a)\frac{1}{3}+\frac{-2}{5}+\frac{1}{6}+\frac{-1}{5}\le x< \frac{-3}{4}+\frac{2}{7}+\frac{-1}{4}+\frac{3}{5}+\frac{5}{7}\)
\(\Rightarrow\frac{1}{3}+\frac{1}{6}+\frac{-2}{5}+\frac{-1}{5}\le x< \frac{-3}{4}+\frac{-1}{4}+\frac{2}{7}+\frac{5}{7}+\frac{3}{5}\)
\(\Rightarrow\frac{2}{6}+\frac{1}{6}+\frac{-3}{5}\le x< -1+1+\frac{3}{5}\)
\(\Rightarrow\frac{1}{2}+\frac{-3}{5}\le x< \frac{3}{5}\)
\(\Rightarrow\frac{-1}{10}\le x< \frac{6}{10}\)
\(\Rightarrow-1\le x< 6\)
\(\Rightarrow x\in\left\{-1;0;1;2;3;4;5\right\}\)
Bài b tương tự
bạn ơi bạn giải câu b được ko. mk ko biết làm câu b
Bài 1 tìm x biết x=\(\frac{2}{3}.S\)
S=\(\frac{\left(9\frac{3}{8}:5.2+3,4.2\frac{7}{34}\right):1\frac{9}{16}}{0,31.8\frac{2}{5}-5,61:27\frac{1}{3}}\)
Tìm 15% của M biết
M=\(\frac{\left(23\frac{11}{15}-26\frac{13}{20}\right)}{12^2+5^2}:\frac{1-\frac{1}{3}-\frac{1}{42}-\frac{1}{56}}{3^2.13.2}-\frac{19}{37}\)
\(S=\frac{\left(9\frac{3}{8}:5,2+3,4.2\frac{7}{34}\right):1\frac{9}{16}}{0,31.8\frac{2}{2}-5,61:27\frac{1}{3}}\)\(\Rightarrow S=\frac{\left(\frac{75}{8}.\frac{5}{26}+\frac{17}{5}.\frac{75}{34}\right):\frac{25}{16}}{\frac{31}{100}.9-\frac{561}{100}.\frac{3}{82}}\)\(\Rightarrow S=\frac{\left(\frac{75.5}{8.26}-\frac{17.75}{5.34}\right).\frac{16}{25}}{\frac{31.9}{100}-\frac{561.3}{100.82}}\)
\(\Rightarrow S=\frac{\left(\frac{375}{208}-\frac{15}{2}\right).\frac{16}{25}}{\frac{279}{100}-\frac{1682}{8200}}\)\(\Rightarrow S=\frac{\frac{-1185}{208}.\frac{16}{25}}{\frac{21196}{8200}}\)\(\Rightarrow S=\frac{-237}{65}:\frac{21196}{8200}\)\(\Rightarrow S=\frac{-194340}{137774}\)
\(\Rightarrow x=\frac{2}{3}S\Rightarrow x=\frac{2}{3}.\frac{-194340}{137774}\Rightarrow x=\frac{-388680}{413322}\)
\(M=\frac{23\frac{11}{15}-26\frac{13}{20}}{12^2+5^2}:\frac{1-\frac{1}{3}-\frac{1}{42}-\frac{1}{56}}{3^2.13.2}-\frac{19}{37}\)\(\Rightarrow M=\frac{\frac{356}{15}-\frac{533}{20}}{12^2+5^2}:\frac{\frac{5}{8}}{3^2.13.2}-\frac{19}{37}\)
\(\Rightarrow M=\frac{\frac{-35}{12}}{12^2+5^2}.\frac{3^2.13.2}{\frac{5}{8}}-\frac{19}{37}\)\(\Rightarrow M=\frac{-84}{13}-\frac{19}{37}\Rightarrow M=\frac{-3355}{481}\Rightarrow15\%M=\frac{-3355}{481}.15\%\Rightarrow15\%M=\frac{-2013}{1924}\)
1, \(Cho:\)\(A=\frac{34}{7.13}+\frac{51}{13.22}+\frac{85}{22.37}+\frac{68}{37.49}\) và \(B=\frac{39}{7.16}+\frac{65}{16.31}+\frac{52}{31.43}+\frac{26}{43.49}\)
\(Tính\)\(A:B\)
2, So sánh 3111 và 1714
3, Tìm p là số nguyên tố sao cho 5p + 3 cũng là số nguyên tố
4, Tìm x, nếu:
\(|x+3|+|x+7|=3.x\)
Tìm x, biết
a/ \(\frac{15}{x}-\frac{1}{3}=\frac{28}{51}\)
b/ \(\frac{x}{20}-\frac{2}{5}=10\)
c/ \(x+\frac{18}{23}=2\frac{1}{3}\)
d/ \(\frac{7}{11}< x-\frac{1}{7}< \frac{10}{13}\)
e/ \(\frac{7}{9}< \frac{13}{11}-x< \frac{15}{16}\)
Cho xin cách giải thik lun nha
a/ \(\frac{15}{x}-\frac{1}{3}=\frac{28}{51}\)
\(\frac{15}{x}=\frac{28}{51}+\frac{1}{3}\)
\(\frac{15}{x}=\frac{15}{17}\)
\(x=15:\frac{15}{17}\)
\(x=17\)
b) \(\frac{x}{20}-\frac{2}{5}=10\)
\(\frac{x}{20}=10+\frac{2}{5}\)
\(\frac{x}{20}=\frac{52}{5}\)
\(x=\frac{52}{5}\cdot20\)
\(x=208\)
c) \(x+\frac{18}{23}=2\frac{1}{3}\)
\(x+\frac{18}{23}=\frac{7}{3}\)
\(x=\frac{7}{3}-\frac{18}{23}\)
\(x=\frac{107}{69}\)
d) \(\frac{7}{11}< x-\frac{1}{7}< \frac{10}{13}\)
\(\Rightarrow\frac{7}{11}+\frac{1}{7}< x< \frac{10}{13}\)
\(\frac{60}{77}< x< \frac{60}{78}\)
Đến đây .....bí!
e) Tớ bỏ luôn đc ko.
D) 7/11<X-1/7<10/13
<=> 7/11+1/7<x< 10/13+1/7
<=> 60/77< x< 83/91
<=> 5460/1001 <x< 6391/1001
vậy X thuộc tập hợp các phÂN số lớn hơn 5460/1001 và bé hơn 913/1001
vd : Y/1001 trong đó y là 5461;5462;5463...6389;6390
e) 7/9<13/11-x<15/16
<=> 7/9-13/11<-x< 15/16 -13/11
<=> -40/99< -x< -43/176
<=> 43/99< x < 40/176( nhân với -1 nên đổi dấu )
<=> 387/1584 < x< 640/1584
<=> vậy X là các phân số có dạng y/1584 , trong đó Y là 388;389;390 ........ 639
Tìm x, biết
a,/\(\frac{13}{11}.\frac{22}{26}-x^2=\frac{7}{16}\)
b,\(^{x^2+\frac{-9}{25}=\frac{2}{5}.\frac{8}{5}}\)
khó quá giúp mk với:))
a/\(\frac{13}{11}.\frac{22}{26}-x^2=\frac{7}{16}\)
\(\Rightarrow1-x^2=\frac{7}{16}\)
\(\Rightarrow x^2=\frac{9}{16}\)
\(\Rightarrow x=\orbr{\begin{cases}\frac{3}{4}\\-\frac{3}{4}\end{cases}}\)
\(a,\frac{13}{11}.\frac{22}{26}-x^2=\frac{7}{16}\)
\(1-x^2=\frac{7}{16}\)
\(x^2=1-\frac{7}{16}=\frac{9}{16}\)
\(\Rightarrow\orbr{\begin{cases}x=\frac{3}{4}\\x=-\frac{3}{4}\end{cases}}\)
\(b,x^2+-\frac{9}{25}=\frac{2}{5}.\frac{8}{5}\)
\(x^2+-\frac{9}{25}=\frac{16}{25}\)
\(x^2=\frac{16}{25}--\frac{9}{25}=1\)
\(\Rightarrow\orbr{\begin{cases}x=1\\x=-1\end{cases}}\)
học tốt ~~~
a/ \(\frac{13}{11}.\frac{22}{26}-x^2=\frac{7}{16}\)
\(\Rightarrow\)\(1-x^2=\frac{7}{16}\)
\(\Rightarrow\)\(x^2=1-\frac{7}{16}\)
\(\Rightarrow\)\(x^2=\frac{9}{16}\)
\(\Rightarrow\)\(x^2=\left(\frac{3}{4}\right)^2\)
\(\Rightarrow\)\(x=\frac{3}{4}\)
b, \(x^2+\frac{-9}{25}=\frac{2}{5}.\frac{8}{5}\)
\(\Rightarrow x^2+\frac{-9}{25}=\frac{16}{25}\)
\(\Rightarrow x^2=\frac{16}{25}-\frac{-9}{25}\)
\(\Rightarrow x^2=\frac{25}{25}\)
\(\Rightarrow x^2=\left(\frac{5}{5}\right)^2=\left(\frac{-5}{5}\right)^2\)
\(\Rightarrow x=\frac{5}{5}=\frac{-5}{5}\)
\(\Rightarrow x=1=-1\)
\(\Rightarrow x=\pm1\)