problem:
Frank has invested € 20 000,- at an interest rate of 3 1/4%.
After 7 months and 5 days he witdrawn all of his money.
a) How much interest does he receive?
b) How much money does he own now?
answer:
1. step: given/wanted
capital: € 20 000,-
interest rate: 3 1/4% = 3,25%
time: 7 months 5 days = 7 * 30 + 5 = 215 days
wanted: interest in € = ?
2. step: calculate
Tom:
i = interest c = capital ir = interest rate d = days
i = c * ir * d : 36 000
i = 20 000 * 3,25 * 215 : 36 000
i = 388,19 €
3. step: answer
Frank receives € 388,19 .
How much money owns Frank now?
total amount: capital + interest
total amount: € 20 000,- + € 388,19
total amount: € 20 388,19
Frank owns € 20 388,19.