\(\frac{6+x}{33}=\frac{7}{11}\)

\(\Rightarrow\left(6+x\right)\times11=33\times7\)

     \(\left(6+x\right)\times11=231\)

    \(6+x=231\div11=21\)

\(\Rightarrow x=21-6=15\)

Vậy \(x=15\)

x=15 nhe

bằng 15

cậu làm được không?

\(\frac{x+6}{33}=\frac{7}{11}\)

33 :3=11

x+6:3=7

7 x 3=21

21-6=15

Vậy\(\frac{15+6}{33}=\frac{7}{11}\)

\(X+6=\frac{7.33}{11}\)

\(X+6=21\)

\(X=21-6\)

\(X=5\)

x=15 nhé

\(\frac{33}{2}+\frac{33}{6}+\frac{33}{18}+\frac{33}{54}+\frac{33}{162}+\frac{33}{486}\)

\(=\frac{33.3+33.3+33.3+33.3+33.3}{486}\)

\(=\frac{99.5}{486}\)

\(=\frac{495}{486}\)

Gọi \(A=\frac{33}{2}+\frac{33}{6}+...+\frac{33}{486}\)

\(A=33.\left[\left(\frac{1}{1.2}+\frac{1}{2.3}\right)+\left(\frac{1}{3.6}+\frac{1}{6.9}\right)\left(\frac{1}{9.18}+\frac{1}{18.27}\right)\right]\)

\(A=33.\left[\frac{2}{3}+\frac{2}{9}+\frac{2}{27}\right]\)

\(A=66.\left[\frac{9}{27}+\frac{3}{27}+\frac{1}{27}\right]\)

\(A=66.\frac{13}{27}\)

\(A=\frac{286}{9}\)

sai hay đúng cx ko biết nha

\(\frac{2}{3.5}+\frac{2}{5.7}+\frac{2}{7.9}+\frac{2}{9.11}+\frac{2}{11.13}+\frac{2}{13.15}\)

\(=1+\frac{2}{3}-\frac{2}{3}+\frac{2}{5}-\frac{2}{5}+....+\frac{2}{15}\)

\(=1+\frac{2}{15}\)

\(=\frac{17}{15}\)

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

\(\frac{33-33:\frac{11}{6}}{\frac{6}{11}}\)

\(=\frac{33-33\cdot\frac{6}{11}}{\frac{6}{11}}\)

\(=\frac{33-33\cdot1}{1}\)

\(=33-33=0\)

\(\frac{33-33:\frac{11}{6}}{\frac{6}{11}}\)

\(=\frac{33-33\cdot\frac{6}{11}}{\frac{6}{11}}\)

\(=\frac{33-18}{\frac{6}{11}}\)

\(=\frac{15}{\frac{6}{11}}\)

\(=\frac{55}{2}\)

* Bấm máy thấy sai xD Sửa lại tí *

\(\frac{33-33:\frac{11}{6}}{\frac{6}{11}}\)

\(=\frac{33-33\cdot\frac{6}{11}}{\frac{6}{11}}\)

\(=\frac{33-\frac{33\cdot6}{11}}{\frac{6}{11}}\)

\(=\frac{33-18}{\frac{6}{11}}\)\\(=\frac{15}{\frac{6}{11}}=\frac{15\cdot11}{6}=\frac{55}{2}\)

\(=\left(-\frac{5}{132}-\frac{5}{3}\right)-\left(-\frac{5}{4}+\frac{6}{11}\right)\)

\(=-\frac{75}{44}-\left(-\frac{5}{4}+\frac{6}{11}\right)\)

\(=-\frac{75}{44}+\frac{31}{44}\)

\(=-1\)

( \(\frac{-1}{4}\)+ \(\frac{7}{33}\)- \(\frac{5}{3}\) ) - ( \(\frac{-5}{4}\) + \(\frac{6}{11}\)) 

= ( \(\frac{-1}{4}\)\(\frac{-48}{33}\)) - ( \(\frac{-31}{44}\))

=  \(\frac{-1}{4}\)+ \(\frac{-48}{33}\)+ \(\frac{-31}{44}\)

= ( \(\frac{-1}{4}\)+ \(\frac{-31}{44}\)) + \(\frac{-48}{33}\)

= \(\frac{-5}{11}\) + \(\frac{-48}{33}\)

=  \(\frac{-21}{11}\)

HỌC TỐT ^^__^^

\(\left(\frac{-1}{4}+\frac{7}{33}-\frac{5}{3}\right)-\left(\frac{-5}{4}+\frac{6}{11}\right)\)

\(=\frac{-1}{4}+\frac{7}{33}-\frac{5}{3}+\frac{5}{4}-\frac{6}{11}\)

\(=\left(\frac{-1}{4}+\frac{5}{4}\right)+\left(\frac{7}{33}-\frac{6}{11}\right)-\frac{5}{3}\)

\(=1+\left(\frac{-1}{3}\right)-\frac{5}{3}=1+\left(\frac{-1}{3}-\frac{5}{3}\right)=1+\left(-2\right)=-1\)

Cậu có thể tham khảo bài làm trên  đây ạ, chúc cậu học tốt^^

làm ơn giúp em giải bài toán này!!!!!!!!

Sorry , I can't do it .

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