Texas Instruments TI Programmable 57 User Manual

A PRACTICAL CASE
You can now goon and pick a’:payment program very carefully, seeing
exactly
how
much
your
interest'charge
will
be
for
each
alternative.
In
this
example
you've
used
your
calculator
to
handle
a
very
important
and
versatile
business
formula.
The
formula
for
calculating
the
amount
of
(equal
monthly)
payments
on
a
credit card
type
of account
is:
i
Payment
=
PV x
(= al
=|
Where: i=the monthly interest rate (1.5% or .015)
n=number of months
PV =the present value of the balance you owe ($500)
The total interest charge in dollars is calculated as:
Total
Interest
Charge
=
(n
x
payment)
—
PV
In
handling
the
problem
above
the
present
value
of
the
balance
owed
(PV)
was
stored
in
memory
1.
The
monthly,
interest
rate
(1%)
was
stored
in
memory
2,
and
the
number
of
months
you
take
(n)
was
stored
in
memory
3:
From
now
on
in
you
can
“try
out”
any
number
of
months
you'd
like
(for
any
present
value,
or
any
interest
rate)
just
by
changing
what
you've
got
stored
in
one
of
the
three
memories,
Your
calculator
does
all
the
work
at
the
touch
of a
key.

Texas Instruments TI Programmable 57 Specifications

General

Brand	Texas Instruments
Model	TI Programmable 57
Category	Calculator
Language	English