Question 746439
Compound interest at 4% = 104/100 = 1.04
 $255 x 1.04^9 = $362.95.
a) $362.95 - $255 = $107.95 (interest at end
  of 9 months)
b)$255 x 1.04^10 = $377.46
  so $377.46 - $362.95 = $14.51 (extra interest
  by extending loan to 10 months)