12-pack for 1.69 is a better buy
Solution:
Given that, Mike bought a 12-pack for 1.69 and Mary bought a 24-pack for 3.18
We have to find which is the better buy
First we have to find the unit rate
Unit rate is cost of 1 pack
Mike bought a 12-pack for 1.69
Therefore,
Cost of 12 pack = 1.69
Cost of 1 pack is found by dividing 1.69 by 12
[tex]cost\ of\ 1\ pack = \frac{1.69}{12} = 0.14083[/tex]
Thus unit rate of Mike is 0.14083 dollar per pack
Mary bought a 24-pack for 3.18
Cost of 24 pack = 3.18
Cost of 1 pack is found by dividing 3.18 by 24
[tex]cost\ of\ 1\ pack = \frac{3.18}{24} = 0.1325[/tex]
Thus unit rate of Mary is 0.1325 dollars
On comparing both the unit rate
[tex]0.14083>0.1325[/tex]
Thus unit rate of Mike is larger
Thus, 12-pack for 1.69 is a better buy