Question

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

Answer 1

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

Answer 2

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