Engineering Economic Analysis

Continuous Compounding 121

MultiplyingEquation 4-43 by the single payment, continuous compoundingfactors, we can

findFfor any future time andPfor any present time.

For Any Future Time

F= 15 (er;1)(er(n-l» =15 [.(er -r~;(ern)]

n

F

Compound amount [Fj15, r, n]=

[

(er -IHern)

rer ]

(4-48)

For Any Present Time

P=F

(

er- 1.

)

(e-rn)=F

[

er- 1

r rern ]

1

p

[

er- 1

]

Presentworth [PjF,r,n] = -rern (4-49).

A self-service gasoline station has been equipped with an automatic teller machine (ATM).Cus-

tomers may obtain gasoline sin!ply byins~rting tpeir ATM bank card into tJ:J.emachine and filling ;::

their tank with gasoline. When they have finished, theATM unit automatically deducts the gasoline

purchaSe from the customer's bank account and credits it to the gas station's bank account. The

ga§ §Ultionres;ejx~~,,"$40,qOO~etmonth.;inthisJIlanner,,,,,with,thecash flowing"uniformly throughout

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I"

I

1

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