Matematika

Pertanyaan

Sarah borrowed RM 20000 from two money lenders. She has to pay simple interest of 12% per annum for one of the loan and 14% per annum for the other. After one year, she paid a total of RM 2560 as interest. How much did she borrow at respective rate?

1 Jawaban

  • If 1st lenders we called A, and 2nd lenders we called B.
    So match equation for Basic loan is A+B = 20.000

    Interest for A = 12%
    So Total paid per annum = 100% +12% = 112%

    interest for B = 14%
    So total pain per annum = 100%+14% = 114%

    Total interest = 2.560
    So total paid = 20.000+2.560 = 22.560

    If total paid A+B = 22.560
    so : 112%A + 114%B = 22.560 then
                   A +         B = 20.000         

    eliminated both equation 
    1,12A + 1,14B = 22.560  Ix1       I 1,12A + 1,14B = 22.560
           A +       B = 20.000  Ix 1,12 I  1,12A + 1,12B = 22.400
                                                     ----------------------------------------- -
                                                                    0,02B = 160
                                                                           B = 160/0,02
                                                                              = 8.000
                                                             A+8.000 = 20.000
                                                                       A = 12.000
         
    Conclution : Borrowed from 1st lenders : RM 12000
                      Borrowed from 2nd lenders : RM  8000

    pls re-check each process of equation before took as final answer.
    Wish helpfull.         

Pertanyaan Lainnya