Question

Afla numerele x si y, stiind ca sunt direct proportionale cu 5 si cu 7, si media lor aritmetica este 29,4.

Answer 1

Răspuns:

Explicație pas cu pas:

x/5=y/7

7x=5y

x+y=58,8

5y/7+y=58,8

12y/7=58,8

y=58,8*7/12

y=34,3

x=5y/7

x=5*34,3/7

x=24,5

Answer 2

Răspuns:

$x/5=y/7=k\\\\x=5k\\\\y=7k\\\\\frac{5k+7k}{2} =29,4= > 12k=29,4*2= > 12k=58,8= > k=58,8:12= > k=4,9\\\\x=5*4,9= > x=24,5\\\\y=7*4,9= > y=34,3$