Question

Determinati x apartine N pentru care 3/5<n+1/15<4/3  Help mee pls!!

Answer 1

x ∈ N 
numitor 15 
3 · 3 < n +1 < 4 ·5 
9 < n +1 < 20 
9 - 1 < n +1 -1 < 20 -1 
8 < n  < 19 
n ∈ { 9;10;11;12;13;14;15;16;17;18}