Răspuns :
(a+b):2=100
a+b=100x2
a+b=200
a=3b
3b+b=200
4b=200
b=200:4
b=50
a=3x50
a=150
V: (150+50):2=200:2=100
a+b=100x2
a+b=200
a=3b
3b+b=200
4b=200
b=200:4
b=50
a=3x50
a=150
V: (150+50):2=200:2=100