Basic Mathematics for College Students

(Nandana) #1

264 Chapter 3 Fractions and Mixed Numbers


Solution
Alw This is the formula for the area of a rectangle.

Substitute for land for w.

Write and as improper fractions.

Write the improper fraction as a mixed number.

The area of the screen of an Etch-a-Sketch is 28 18 in.^2.

225
 28 8

1


8


28
8  225
 16
65
 64
1

Since there are no common factors to remove,
perform the multiplication in the numerator and in
the denominator. The result is an improper fraction.




225


8


Multiply the numerators.
 Multiply the denominators.

25  9


4  2


 6 41 4 21


25


4





9


2


 6 6 14 4 21


1


4


 4


1


2


EXAMPLE (^8) Government Grants If million is to be split equally
among five cities to fund recreation programs, how much will each city receive?
Analyze



  • There is million in grant money. Given

  • 5 cities will split the money equally. Given

  • How much grant money will each city receive? Find
    Form The key phrase split equallysuggests division.
    We translate the words of the problem to numbers and symbols.


is equal to divided by

 5


SolveTo find the quotient, we will express and 5 as fractions and then use the
rule for dividing two fractions.

Write as an improper fraction, and write 5 as a fraction.

Multiply by the reciprocal of , which is.

Write the improper fraction as a mixed number
by dividing 5 by 2. The units are in millions of dollars.

5
 2 1 2
2

Multiply the remaining factors in the numerator.

 (^) Multiply the remaining factors in the denominator.


5


2


To simplify, factor 25 as 55. Then remove the common

 (^) factor of 5 from the numerator and denominator.


5


1
 5  1
2  5
1

Multiply the numerators.

 (^) Multiply the denominators.


25  1


2  5


1
5

5
 1

25


2





1


5


12 12 21


1


2


 5 


25


2





5


1


12 12


12 


1


2


The amount of
money that each
city will receive (in
millions of dollars)

the number of
cities receiving
money.

the total amount
of grant money
(in millions
of dollars)

The amount of
money that each
city will receive (in
millions of dollars)

$12 12


$12 12


Self Check 8
TV INTERVIEWSAn -minute
taped interview with an actor
was played in equally long
segments over 5 consecutive
nights on a celebrity news
program. How long was each
interview segment?
Now TryProblem 107

18 34

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