Enhancing Learning With a Graphics Calculator - CasioEd

Enhancing learning with a graphics calculator
Example 2. Ben invests $100 every quarter in a bank account earning 12% p.a.
compounded quarterly. Copy and complete the following table.
Quarter Amount at Beginning of Interest Amount at End of
Quarter
Quarter
1 $100 $3 $103
2
3
4
$203
Rewrite the table as for Question 1, and use your calculator to answer the following
questions:
(a) check the amount in the account at the beginning of quarter 3.
(b) check the amount in the account at the end of year 1.
(c) find the amount in the account at the beginning of year 3.
(d) find the amount in the account at the end of year 5.
Example 3. On every birthday, Carolyn receives $50 by her husband. On her 35 th
birthday she decides to invest her money and all future money into an annuity earning
10% p.a. Use your calculator to develop a table as in Questions 1 and 2, and use that
table to find:
(a) the amount Carolyn has in the account just before her 40th birthday.
(b) how much she has in the account just after her 50th birthday.
Example 4. Peter needs to save a total of $20 000 for a trip to Europe. He invests in
an annuity, which pays 6 % p.a. compounded monthly. He pays $250 every month into
the annuity. Fill in the first 4 months of the table showing this.
Month Balance after Deposit Balance + Interest
1 250 251.25
2 501.25
3
4
(a) Write the recursive formula for this annuity where a n is the balance after his n th
deposit and a n+1 is the next balance.
(b) How long will it take Peter to save the required amount for his trip?
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