Normal SP $11 Contract price $9 Unit cost $6 Unit cost $6 Cont/ unit $5 Cont / unit $3 1st column: 300u/400u (400u x $5) + (300u x $3) =$2900 500u/400u (400u x $5) + (500u x $3) =$3500
You continue like this to the end and then you move to the next column i.e. 300u/500u and then it’s pretty much the same as above. Hope this helps!