Question

Media aritmetica a sapte numere naturale nenule consecutive este 18.Calculati numerele.

Answer 1

(a+a+1+a+2+a+3+a+4+a+5+a+6)/7=18
7a+21=126
7a=105
a=15
a+1=16
a+2=17
a+3=18
a+4=19
a+5=20
a+6=21

Answer 2

a->primul nr.=15
a+1->al II-lea nr.=15+1=16
a+2->al III-lea nr.=15+2=17
a+3->al IV-lea nr.=15+3=18
a+4->al V-lea nr.=15+4=19
a+5->al VI-lea nr.=15+5=20
a+6->al VII-lea nr=15+6=21
[tex]M_a= \frac{a+a+1+a+2+a+3+a+4+a+5+a+6}{7}=18 \\\\ 18= \frac{7a+21}{7} \\\\ 7a+21=18*7\\ 7a+21=126\\ 7a=126-21\\ 7a=105\\ a= \frac{105}{7} \\ \boxed{a=15}\\ [/tex]