Math 141, Sem. I, 1998-99 (R.A. Brualdi)
Handout 13 (October 23, 1998)
Topic: Quiz # 4 (10 points per problem)
1. At 9:00 AM, a super-car starts from rest at the 10 mile marker on a
road, accelerating at a constant rate of 100 mph^2. Exactly at noon, the
car changes from accelerating to deccelerating at 30 mph^2 until it halts.
(a) At what mile marker is the car at noon, and what speed?
(b) At what mile marker is the car at 2 PM, and what speed?
(c) At what time and at what mile marker does the car come to a halt
[Answers correct to two decimal places, time within 2 nminutes.]
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Scratch work - I will not read this.
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Polished solution:
2) Each year the population of a country, whose population on January 1,
1998 is 585,000 increases by 8%.
(a) What is the population on October 1, 2000?
(b) When does the population reach 1,000,000? [I would like the month and
day of the month given by this model. You may assume that a year is 360
days long with 30 days in each month. I expect your answer to be no more
than two days off.]
(c) What percentage rate of growth would ensure that the population in
eight years is 750,000?
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Scratch work - I will not read this.
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Polished solution: