you would do:
3.32 divided by 12 = 0.276 reccuring
then do 3.80 divided by 16 = 0.2375 ( these are the prices each pr fl. )
Then compare the numbers together
0.276
0.2375
if you look the top one goes 2 then seven while the bottom one goes two then 3 so the bottom one is the lat expensive
hope this help
