Verified Answer :

a.sinceĀ 
108-$25.18
1 diaper=?
$
25.18 divided by 108=$0.233

b.since
180 - $
39.14
1 diaper=?
therefore, $39.14 divided by 180=$0.217

c.since
160 diapers - $38.77
1 diaper will be $
38.77 dollars divided by 160=$0.243

d.i will advice her to buy the third type of diapers since that contains many diapers