Engineering Economy 1 / 2
-
SIMPLEINTEREST
- "¥ basisofinterestisalwaystheinitial amount Solh
:69
- O
31 100
°i 2 3n F=p ( It rn ) ll l 7 # ... I > n , period , I * assume ordinarysimple ti t !( year , month , etc ) pN # / interest ,unless specified l l l l = F - D
where: u
v ' ' l l I = Prn * eco .o, )f Aassume annualinterest P I l l l P - - 0.97F rate , unless specified PtPrl llD - - 0.03ft l l TI Ptprcz ) l l netinterest
:
trI Ptprl's 1 , I ' = I - T I = Prn + Ptprn - -F
0.03¥
:
0.97 #4) ( ¥0) r - -
0.1614
or
16.14%
*2TypesofsimpleInterest * • Ordinary "¥ assumes thatthere are 30 days )month or 360days in a year , calledthe " banker 'srule " Solh
:
• Exact I ' - - I - T "¥ assumes theexactdays in a year890.36 i I -
0.2015
wk is365 (regular) and366 (leapyear ) I - -
1112.95
SAMPLEPROBLEMS
:
I = Prn
1112.95--110000(
r )(}÷o) r
:
0.1175
I
11.75%
Solh
:
From May1,2002 toMay1,2005 = 3 ( 360 ) FromMay I , 2005 toAug .
1,2005
:
90 1170 days I
:
Prn =
250006.08
)(
'317600
) I - - 6,500 Solh
:
May I ,
20021365
May1,2003 May
1,20041366
May
1,20051365
May 131 ) August1,2005 !Junko) July( 31 ) 1188days I - - Prn '
25.0001000
)( "8386¥ ) I
:
6,504.11
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