Answer:
Shampoo one is a better buy
Explanation:
Step one:
given data
The 16 fl oz. Cost $6.19 and
The 13.5 fl oz. Cost $ 3.99
Required
The better buy/ unit cost
Step two:
shampoo one
unit cost = 16/6.19
=$2.58 per fl oz
shampoo two
unit cost = 13.5/3.99
=$3.38 per fl oz