kill(all)$

narrowShelfWidth:35.78;

narrowShelfCost: 39.99;

wideShelfWidth:47.625;

wideShelfCost: 53.99;

160/narrowShelfWidth;

160/wideShelfWidth;

f(a,b):=a*narrowShelfWidth+b*wideShelfWidth;

c(a,b):=a*narrowShelfCost+b*wideShelfCost;

for a: 1 thru 10 do
    for b: 1 thru 10 do
        if f(a,b) <= 160 then print("a: ", a, "  b: ", b, "  total width: ", f(a,b), "   COST: ", 0.95*c(a,b));

0.05*c(3,1);