Question

Daca nr. A si B sun invers proportionale cu nr. 5 si 8 calculati valoarea raportului (3a + 7b) / 7b

Answer 1

{a,b}i.p.{5,8}
=>5a=8b=k
a=k/5 si b=k/8

(3a+7b)/7b=3a/7b+7b/7b=3a/7b  + 1
3a/7b  + 1=(3k/5)/(7k/8)  + 1= 24/35  + 35/35= 59/35
R: 59/35