-c +4d
Step-by-step explanation:

Group like terms and simplify

APR=18%
Monthly interest = 18/12=1.5%
If Caitlyn paid before due date,
amount liable for interest charges = 375-250 = $125
Interest charge for the month
=$125*1.5%
=$1.88
If a single expression is required, then
interest = (375-250)*0.018/12 = $1.88 to the nearest cent.
9/10 divided by 3/12
Find the least common multiple
54/60 divided by 15/60
Flip the second fraction and transition from division to multipication
54/60*60/15
Final answer: 3.6 or 3 3/5