Question

Fie a,b,c trei numere naturale astfel incat 3a+b=79, si 6a+2b+3c=200. aflati valoarea numarului 15a+5b+2c

Answer 1

6a+2b+3c-2(3a+b)=3c=200-2*79
3c=200-158
3c=42
c=14
15a+5b+2c= 5(3a+b) +2c=5*79+2*14=423

Answer 2

6a + 2b + 3c = 200
2(3a + b) + 3c = 200
2 * 79 + 3c = 200
3c = 200 - 158
c = 42 : 3
c = 14
15a + 5b + 2c =
5(3a + b) + 2 * 14 =
5 * 79 + 28 =
423