A bottle contains 20 fluid ounces of lotion and sells for $5.80. The 20-fluid-ounce bottle contains 125% of the lotion in the next smallest size, which sells for $5.12. Which is the better buy? Explain

Here is a way to solve wihtout knowning the volume of the smaller bottle (which is 16oz, btw)

if 5.8 is 125% of the volume of the other one

find what it would cost for 100%

5.8=125% of volume

1.16=25% of volume

4.64

that contains the sameamount as theother one

4.64<5.12

the 20 oz bottle is the better buy

don't believe me?

20=125% of other

4=25% of other

16=100% of other

let's find the cost per ounce of lotion

5.8/20?5.12/16 where? represents a relation symbol (=,> <)

0.29?0.32

0.29<0.32

20 oz bottle is the better buy

The 20 fluid ounce because you get more for. 78 cents more