Răspuns:
30
Explicație pas cu pas:
[tex]e:4 = c_1 \text{ rest 2} \\ e:7 = c_2\text{ rest 2}\\ \\ e = 4c_1+2\\ e = 7c_2+2 \\ \\ (e-e) = 4c_1-7c_2+2-2 \\ 0 = 4c_1-7c_2 \\ 4c_1 = 7c_2 \\ \\ \dfrac{c_1}{c_2} = \dfrac{7}{4}\\ \\ (1)\quad c_1 = 7,~~c_2 = 4 \Rightarrow e = 4\cdot 7+2 = 30\in [15,40] \\ (2)~~c_1 = 14,~~c_2 = 8 \Rightarrow e = 4\cdot 14+2 = 58 \notin[15,40] \\ \\ \Rightarrow \boxed{e = 30}[/tex]
