Пожалуйста помогите! Напишите пример в столбик! 809*350, 701*235, 406*502

<span>(3/11)s=s1</span>
<span>(7/20)(s-3/11s)=s2</span>
<span>(7/20)(8/11)s=s2</span>
<span>(14/55)s=s2</span>
<span>(5/13)(s-(3/11)s-(14/55)s)=s3</span>
<span>(2/11)s=s3</span>
<span>S=s1+s2+s3+320</span>
<span>s-(s1+s2+s3+320)=0</span>
<span>s-(3/11)s-(14/55)s-(2/11)s-320=0</span>
<span>(6/11)s-(14/55)s-320=0</span>
<span>(16/55)s=320</span>
<span>s=20*55=1100км</span>