Tim

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Tim Toms Financial Adventure

• Philip Rash
• NC School of Science Math
• rash_at_ncssm.edu
• 2009 TCM Conference, Durham NC

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Tim Tom are twins, each of whom begins work
when he turns 20 years old. Each receives a 2000
bonus on his birthday. This continues until each
retires at age 65.
Tim Conservative early in life, each year he
invests his 2000 bonus in a savings program
earning 9 interest annually. On his 30th
birthday, Tim decides to have some fun in life
and he begins spending his 2000 bonuses on
vacations in Hawaii. The money he had already
saved stays in the savings plan and continues to
earn interest.
Tom Believing in his youth that life was too
short to be concerned about saving for the
future, he spends his 2000 bonuses on vacations
in Hawaii. On his 30th birthday, he realizes
that someday he might not be able to work and
then he would need savings to support himself
after retiring. He begins investing his 2000
bonuses in a savings account earning 9 interest
annually.
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• So, how much money do Tim Tom each have when
  they retire?

Source Contemporary Precalculus, page 186,
problem 7 Original Source Smith, Keith, Tim
and Toms Financial Adventure Pull-Out,
Consortium, Number 38, Fall 1991, COMAP, Inc.,
Lexington, MA
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Recursive Solution

Tim
bday A B timdep timbal
21 0 2000 2000
22 1 2000 4180

28 7 2000 22056.9
29 8 0 2000 26042.1
30 1 28385.9

64 35 531622
65 36 579468
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Recursive Solution


Tom
bday C tomdep tombal
30 0 2000 2000
31 1 2000 4180
32 2 2000 6556.2

65 35 2000 472249