Question

Jamal borrowed 4000 to buy a used car he borrowed some of the money from a bank that charged 9.2% simple interest and the rest from a friend who charged 12% simple interest. If the total interest for a one year loan was 424.00 how much did jamal borrow at each rate

Answer 1

2000 ; 2000

Explanation:

Given the following :

Total amount borrowed = 4000

Total interést paid = 424

Simple interést = (principal * rate * time)

Rate 1 = 9.2% = 0.092

Rate 2 = 12% = 0.12

Let amount borrowed at 9.2% = x

Amount borrowed at 12% = y

x + y = 4000 - - - - (1)

x * 0.092 + y * 0.12 = 424

0.092x + 0.12y = 424 - - - - (2)

from (1):

x = 4000 - y

0.092(4000 - y) + 0.12y = 424

368 - 0.092y + 0.12y = 424

368 + 0.028y = 424

0.028y = 424 - 368

0.028y = 56

y = 56/0.028

y = 2000

x + y = 4000

x = 4000 - 2000

x = 2000