xxx/3=24

xxx=24 x 3

xxx=72

x=72/3

x=24

cảm ơn nhé

không có chi

\(\frac{24+x}{50+x}=\frac{3}{5}\Rightarrow\left(24+x\right)\cdot5=\left(50+x\right)\cdot3\)3 

hay \(120+24x=150+50x\)

suy ra 50x-24x=150-120 hay 26x = 30 \(\Rightarrow x=\frac{26}{30}\)

=>5x-19+3x+24=125

=>8x+5=125

hay x=15

( 5 x − 19 ) + ( 3 x + 24 ) = 125

. 5 x − 19 + 3 x + 24 = 125

8 x + 5 = 125

8 x = 120

x = 15

\(a)x=\dfrac{1}{4}+\dfrac{5}{13}=\dfrac{33}{52}.\\ b)\dfrac{x}{3}=\dfrac{2}{3}+\dfrac{-1}{7}.\\ \Leftrightarrow\dfrac{x}{3}=\dfrac{11}{21}.\\ \Leftrightarrow\dfrac{7x}{21}=\dfrac{11}{21}.\\ \Rightarrow7x=11.\\ \Leftrightarrow x=\dfrac{11}{7}.\\ c)\dfrac{x}{3}=\dfrac{16}{24}+\dfrac{24}{36}=\dfrac{2}{3}+\dfrac{2}{3}=\dfrac{4}{3}.\\ \Rightarrow x=4.\\ d)\dfrac{x}{15}=\dfrac{1}{5}+\dfrac{2}{3}=\dfrac{13}{15}.\\ \Rightarrow x=13.\)

x=18 nha

x+x/3=24

3x/3+x/3=24

3x+x/3=24

x(3+1)=72

4x=72

x=72:4

x=18

mọi số tự nhiên đều có thể viết dưới dạng phân số có mâu số là 1 

vậy x/1 = x/3 = 24 

=> 3x/3 + x/3 = 24

                4x/3 = 24 

                  4x = 72 

                    x =18

\(x+\frac{x}{3}=24\)

\(\frac{4x}{3}=24\)

=> \(x=24:\frac{4}{3}=18\)

=> 3x+x=72 => 4x=72 => x=18

\(x+\frac{x}{3}=24\)  

=> \(\frac{3x+x}{3}=24\) 

=> \(4x=72\) <=> \(x=18\)

\(x+\frac{x}{3}=24\)

\(\Rightarrow\frac{3x}{3}+\frac{x}{3}=24\)

\(\Rightarrow\frac{3x+x}{3}=24\)

\(\Rightarrow\frac{4x}{3}=24\)

\(\Rightarrow4x=24\times3=72\)

\(\Rightarrow x=72:4=18\)