Mr. Steiner needs to purchase 60 AA batteries. A nearby store sells a 20-pack of AA batteries for $12.49 and a 12-pack of the same batteries for $7.20. i. Would it be less expensive for Mr. Steiner to purchase the batteries in 20-packs or 12-packs? ii. What is the difference between the costs of one battery from each pack?
Mathematics · Middle School · Tue Nov 03 2020
Answered on
Given :
Batteries needed to purchase = 60
Cost of 20-pack of AA batteries = $12.49
Cost of 12-pack of AA batteries = $7.20
So, Number of 20-pack batteries required to buy 60 batteries = 60/20
= 3
Number of 12-pack batteries required to buy 60 batteries = 60/12
= 5
i. Cost of buying 3 packs of 20-pack batteries = 3 × $12.49
= $37.47
And, Cost of buying 5 packs of 12-pack batteries = 5 × $7.20
= $36.00
Hence, it is less expensive to buy 5 packs of 12-pack batteries than 3 packs of 20-pack batteries.
ii.
Cost of 1 20-pack battery = $12.49/20
= $0.6245
And, Cost of 1 12-pack battery = $7.20/12
= $0.6
So, difference = $(0.6245 - 0.6)
= $ 0.0245