I 3/7x⇒150000
II (x-3/7x)*5/8⇒4/7x*5/8=5/14x 75000+1/7x⇒125000
III (x-3/7x-5/14x)*1/3⇒3/14x*1/3=1/14x⇒25000
IV x-3/7x-5/14x-1/14x=1/7x⇒50000
x=3/7x+75000+1/7x+1/14x+1/7x
x-3/7x-2/7x-1/14x=75000
(14x-10x-x)/14=75000
3x/14=75000
x=75000*14/3
x=25000*14
x=350000m²