Question

numerele a,b,c sunt direct proportionale cu 2,3,5 .Aflati numele stiind ca 4a+2b+3c=87

Answer 1

a/2=b/3=c/5=k ⇒
a=2k  ; b=3k  ;c=5k
4×2k+2×3k+3×5k=87
8k+6k+15k=87
29k=87
k=87÷29
k=3
a=2k⇒ a=2·3⇒ a=6
b=3k⇒ b=3··3 ⇒b=9
c=5k ⇒c=5·3 ⇒c=15

Answer 2

a,b,c direct proporționale cu 2,3,5
4a+2b+3c=87
------------------------------------
a/2=b/3=c/5=k
a=2k
b=3k
c=5k
4*2k+2*3k+3*5k=87
29k=87
k=87:29
k=3
a=2k=2*3=6
b=3k=3*3=9
c=5k=3*5=15