Question

dauva rog. ex 1 2 3 4 5 si 6. 20 puncte si coroana

Answer 1

1-nu stiu
2.ab+ac=145
a(b+c)=145
5(b+c)=145|:5
《 b+c=29
《 c=b+1 (nr.consecutive) =>
=>b+b+1=145=>2b+1=145=>2b=144=>
=>b=72
3.11+22+33+44+55+66+77+88+99+111+222+333+444+555+666+777+888+999=5490

4 si 5 nu stiu