pc2-3-Applications of Equations

Applications of
Lesson 2.3
What are we doing?
Basically, everything we learned
in the previous two lessons will
be applied to real world
situations or unique situations
that will call upon our newly
gained knowledge
The average of two real
numbers is 39.625, and one
number is 1500 times the
reciprocal of the other. Find the
two numbers.
Yet another example
The width of a rectangle is three
times its height. If it has an area
of 60.75 square feet, what are
its dimensions?
Example Number 3
A storage locker in
the shape of a
rectangular prism with
a square floor has a
volume of 70,000
cubic inches. If the
surface area of the
four walls and the top
is 10,000 square
inches, what are the
dimensions of the
I = PRT {Simple Interest}
I  Interest {fee paid for use of
P  Principal {amount put in}
r  rate {annual interest rate}
t  time {represented in years}
A real estate investment yields a
return of 10% per year and a
certificate of deposit (CD) pays
6% interest per year. How much
of $7500 should be put in the
real estate investment and how
much should be put in the CD to
obtain a return of 7% on the
entire $7500?
A pilot wants to make an 840
mile round trip form Cleveland to
Peoria and back in 5 hours
flying time. There will be a
headwind of 30 mph going to
Peoria, and it is estimated that
there will be a 40-mph tailwind
returning to Cleveland. At what
constant engine speed should
the plane be flown?
All about the examples
A car radiator contains 12 quarts
of fluid, 20% of which is
antifreeze. How much fluid
should be drained and replaced
with pure antifreeze so the
resulting mixture is 50%
Last One, I promise!
A container in the shape of a
rectangular prism with no top
that has a volume of 650 cubic
inches is to be constructed from
a 28 x 20 inch piece of sheet
metal by cutting squares of
equal size from each corner and
folding up the flaps. What size
square should be cut from each