Question

trei nr sunt direct proportionale cu 2 3 5. media lor aritmetica este 46. aflati nr

Answer 1

x/2=y/3=z/5=k x+y+z=138 x=2k,y=3k,z=5k 2k+3k+5k =13810k=138,k=138/10=13,8 x=2*13,8=27,6,y=3*13,8=51,4,z=5*13,8=69

Answer 2

a/2=b/3=c/5=k⇒a=2k,b=3k  si c=5k
(a+b+c):3=46⇒a+b+c=46×3⇒a+b+c=138
2k+3k+5k=138
10k=138
k=138/10
a=2k=2×138/10=276/10
b=3k=3×138/10=414/10
c=5k=5×138/10=690/10
verificare
(a+b+c):3=46
(a+b+c)=46×3
(276+414+690)/10=138
138=138
deci a=276/10
b=414/10
c=690/10