Răspuns :
a+a+2+a+4+a+6+a+8=120
5a = 120-(2+4+6+8)
5a = 120-20
5a = 100
a = 100:5
a = 20
a+2 = 22
a+4 = 24
a+6 = 26
a+8 = 28
5a = 120-(2+4+6+8)
5a = 120-20
5a = 100
a = 100:5
a = 20
a+2 = 22
a+4 = 24
a+6 = 26
a+8 = 28
a+a+2+a+4+a+6+a+8=120
a+b+c+d+e=120
5a+20=120
5a=120-20
5a=100
a=100:5
a=20
b=22
c=24
b=26
e=28