Shale Oil refinery blends two petroleumstocks,A and B, to produce two high-octane gasoline products,I and II. Stocks A and B are produced at the maximum rates of450 and 700
bbUhour,respectively.The corresponding octane numbers are 98 and 89, and the vapor pressures are 10 and 8 Ib/in2
. Gasoline I and gasoline II must have octane numbers of at least 91
and 93,respectively.The vapor pressure associated with both productsshould not exceed
12 Ib/in2
.The profits per bbl ofI and II are $7 and $10,respectively. Determine the optimum
production rate for I and II and their blend ratiosfrom stocksA and B.(Hint:Vapor pressure,
like the octane number, isthe weighted average ofthe vapor pressures ofthe blended stocks.)