North Seattle Community College
Winter Quarter 2012
PRECALCULUS II
Sections: 4.7, 4.8, 10.1, 10.2, 10.6, 11.1
STUDENT NAME: __________________________
QUIZ SCORE: ______________________________
Question 1:
a) A department store charges 1.25% interest per month on the unpaid balance
for customers with charge accounts (interest is compounded monthly). A
customer charges $ 200 and does not pay her bill for 6 months. What is the
bill at that time?
b) A pizza pan is removed at 5: 00 PM from an oven whose temperature is fixed
at 450° F into a room that is a constant 70° F. After 5 minutes, the pan is 300°
F?
i. At what time is the temperature of the pan 135° F?
ii. Determine the time that needs to elapse before the pan is 160° F.
iii. What do you notice about the temperature as time passes?
[Use Newton’s low of cooling: u(t)= T + (u0 – T) ekt k<0 ]
Question 2
I Solve this system of equations using:
a) Method of elimination.
b) Matrix method by reducing to row echelon form.
Question 3:
(b) Carletta has $ 10,000 to invest. As her financial consultant, you recommend
that she invest in Treasury bills that yield 6%, Treasury bonds that yield 7%,
and corporate bonds that yield 8%. Carletta wants to have an annual income
of $ 680, and the amount invested in corporate bonds must be half that
invested in Treasury bills. Find the amount in each investment.
(c) Solve the following set of nonlinear equations
Question 4
(a) First 5 terms for:
2𝑛
(i) (𝑛+3)!
(ii)
3
𝑛2
(b) This sequence is defined recursively, write the first five terms:
(c) 1, 5, 9, 13, 17, …
(d) Write out the sum. Do not evaluate.