Question

suma a trei numere naturale este 90 aflati numerele stiind ca sunt direct proportionate cu 5 ,12 ,13

Answer 1

a/5=b/12=c/13=k
a/5=5k
b/12=12k
c/13=13K
a+b+c=90
5k+12k+13k=90
30k=90
k=90/30
k=3
a=5*3=15
b=12*3=36
c=13*3=39
15+36+39=90