After 5 years she will pay $7,200 in interest.
After 3 years she will pay $4,320 in interest.
Interest saved is 7,200-4,320 = $2880
A= P(1+rt)
where A is the total amount accrued, principal plus interest.
r is the interest rate
P is the amount invested or owed.
and t is the time period.
www.calculatorsoup.com (search for simple interest)
