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.
289 square root = 17
17*17=289
Say 17 was length and 17 was width. L*w=289
Also, all sides of the square are the same.