Question

Suma a trei numere naturale este 90. Aflati numerele, stiind ca sunt direct proportionale cu 5,12,13

Answer 1

a+b+c = 90
a/5=b/12=c/13 = k
a/5 = k, a = 5k
b/12 = k, b = 12k
c/13 = k, c = 13k
5k+12k+13k = 90
30k = 90
k = 90:30
k = 3
a = 5k = 5*3 = 15
b = 12k = 12*3 = 36
c = 13k = 13*3 = 39
V: 15+36+39 = 51+39 = 90