Решите пропорции.

Решаем пропорции:

1. 
   Д:
   
   
   
   • 
     0,4 : y = 2 : 9
     
   
   
   • 
     y = (0,4 * 9) / 2
     
   
   
   • 
     y = 3,6 / 2
     
   
   
   • 
     \(y = 1,8\)
     
   
   
   
   


2. 
   Е:
   
   
   
   • 
     \(\frac{x}{6} = \frac{5,1}{17}\)
     
   
   
   • \(x = \frac{6 \cdot 5,1}{17}\)
   
   
   • \(x = \frac{30,6}{17}\)
   
   
   • \(x = 1,8\)
   
   
   
   


3. 
   Ж:
   
   
   
   • 
     6 : 7 = x : 0,7
     
   
   
   • 
     \(x = \frac{6 \cdot 0,7}{7}\)
     
   
   
   • \(x = \frac{4,2}{7}\)
   
   
   • \(x = 0,6\)
   
   
   
   


4. 
   3:
   
   
   
   • 
     \(\frac{5,4}{18} = \frac{b}{7}\)
     
   
   
   • 
     \(b = \frac{5,4 \cdot 7}{18}\)
     
   
   
   • 
     \(b = \frac{37,8}{18}\)
     
   
   
   • 
     \(b = 2,1\)
     
   
   
   
   


5. 
   Д:
   
   
   
   • 13 : 15 = 2,6 : x
   
   
   • \[x = \frac{15 \cdot 2,6}{13}\]
   
   
   • \(x = \frac{39}{13}\)
   
   
   • \(x = 3\)
   
   
   
   


6. 
   Е:
   
   
   
   • \[\frac{13}{x} = \frac{7}{1,4}\]
   
   
   • \(x = \frac{13 \cdot 1,4}{7}\)
   
   
   • \(x = \frac{18,2}{7}\)
   
   
   • \(x = 2,6\)
   
   
   
   


7. 
   Ж:
   
   
   
   • \[\frac{11}{5,5} = \frac{16}{c}\]
   
   
   • \(c = \frac{16 \cdot 5,5}{11}\)
   
   
   • \(c = \frac{88}{11}\)
   
   
   • \(c = 8\)
   
   
   
   


8. 
   3:
   
   
   
   • a : 0,5 = 7 : 5
   
   
   • \(a = \frac{0,5 \cdot 7}{5}\)
   
   
   • \(a = \frac{3,5}{5}\)
   
   
   • \(a = 0,7\)
   
   
   
   


9. 
   Д:
   
   
   
   • 13 : 20 = 2,6 : a
   
   
   • \(a = \frac{20 \cdot 2,6}{13}\)
   
   
   • \(a = \frac{52}{13}\)
   
   
   • \(a = 4\)
   
   
   
   


10. 
    Е:
    
    
    
    • 14 : 9 = y : 1,8
    
    
    • \(y = \frac{14 \cdot 1,8}{9}\)
    
    
    • \(y = \frac{25,2}{9}\)
    
    
    • \(y = 2,8\)
    
    
    
    


11. 
    Ж:
    
    
    
    • \[\frac{3,8}{19} = \frac{y}{3}\]
    
    
    • \(y = \frac{3,8 \cdot 3}{19}\)
    
    
    • \(y = \frac{11,4}{19}\)
    
    
    • \(y = 0,6\)
    
    
    
    


12. 
    3:
    
    
    
    • \[\frac{a}{13} = \frac{3,2}{14}\]
    
    
    • \(a = \frac{13 \cdot 3,2}{14}\)
    
    
    • \(a = \frac{41,6}{14}\)
    
    
    • \(a = 2,97\) (округлённо)