So you need to compute all the rates to see which is the best deal.
$1.79/12.5ft^2=$0.1432 per ft^2
$5.29/40ft^2=$0.13225 per ft^2
$8.49/50ft^2=$0.1698 per ft^2
$6/60ft^2=$0.10 per ft^2
So the last option is the cheapes per square foot and thus is the best deal. Ordered from least to greatest.
Sherbert, blue, red, and green
