Răspuns:
Explicație pas cu pas:
3.
a) [tex]6\frac{x}{10} = \frac{67}{10}[/tex]
[tex]\frac{6*10 + x}{10} = \frac{67}{10}[/tex]
10* (60+x) = 67*10
600 + 10x = 670
10x = 670 - 600
10x = 70
x = [tex]\frac{70}{10} = 7[/tex]
b) [tex]x\frac{5}{13} = \frac{109}{13}[/tex]
[tex]\frac{x*13 + 5}{13} = \frac{109}{13}[/tex]
13*(13x+5) = 13*109
169x + 65 = 1417
169x = 1417 - 65
169x = 1352
x = 1352 : 169
x = 8
