Question

Suma a patru nr naturale este 67.Daca din fiecare se scade acelasi nr,se obtin-9,15,11,12.Afla cele 4 nr?ms

Answer 1

a+b+c+d=67
⇒a=y+9;
⇒b=y+15;
⇒c=y+11;
⇒d=y+12;
⇒y+9+y+15+y+11+y+12=67
⇒4y+47=67
⇒4y=67-47
⇒4y=20
⇒y=20/4
⇒y=5;
⇒a=5+9=14;
⇒b=5+15=20;
⇒c=5+11=16;
⇒d=5+12=17;

Answer 2

a+b+c+d=67
a-n=9
b-n=15
c-n=11
d-n=12
---------(+)
a+b+c+d-4n=47
67-4n=47
4n=20=>n=5
a=9+5=14
b=15+5=20
c=11+5=16
d=12+5=17