Basic Mathematics for College Students

105. GARDENING Two brands of replacement line for
     a lawn trimmer shown below are labeled in different
     ways. On one package, the line’s thickness is
     expressed as a decimal; on the other, as a fraction.
     Which line is thicker?
     110. FORESTRY A command post asked each of three
     fire crews to estimate the length of the fire line they
     were fighting. Their reports came back in different
     forms, as shown. Find the perimeter of the fire.
     Round to the nearest tenth.

4.5 Fractions and Decimals 385

NYLON LINE

Thickness:

0.065 in.

TRIMMER

LINE

–– 403 in. thick

106. AUTO MECHANICS While doing a tune-up, a
     mechanic checks the gap on one of the spark plugs
     of a car to be sure it is firing correctly. The owner’s
     manual states that the gap should be inch. The
     gauge the mechanic uses to check the gap is in
     decimal notation; it registers 0.025 inch. Is the spark
     plug gap too large or too small?


107. HORSE RACING In thoroughbred racing, the
     time a horse takes to run a given distance is
     measured using fifths of a second. For example, :23^2
     (read “twenty-three and two”) means seconds.
     The illustration below lists four split times for a
     horse named Speedy Flightin a -mile race.
     Express each split time in decimal form.

1 161

(^23 25)
2
125
Speedy Flight Turfway Park, Ky 3-year–old
17 May 2010
Splits
1 mile–– 161
:23^2 :23^4 :24^1 :32^3

108. GEOLOGY A geologist weighed a rock sample at
     the site where it was discovered and found it to
     weigh lb. Later, a more accurate digital scale in
     the laboratory gave the weight as 17.671 lb. What is
     the difference in the two measurements?


109. WINDOW REPLACEMENTS The amount of
     sunlight that comes into a room depends on the area
     of the windows in the room. What is the area of the
     window shown below? (Hint:Use the formula
     A^12 bh.)

(^17 78)
6 in.
5.2 in.
1 mile^1 – 8
1 mile^2 – 3
North flank 1.9 mi
West flank
East flank

111. DELICATESSENS A shopper purchased pound^23
     of green olives, priced at $4.14 per pound, and
     pound of smoked ham, selling for $5.68 per pound.
     Find the total cost of these items.


112. CHOCOLATE A shopper purchased pound
     of dark chocolate, priced at $8.60 per pound, and
     pound of milk chocolate, selling for $5.25 per
     pound. Find the total cost of these items.

WRITING

113. Explain the procedure used to write a fraction in
     decimal form.


114. How does the terminating decimal 0.5 differ from
     the repeating decimal?


115. A student represented the repeating decimal
     0.1333... as. Is this the best form? Explain
     why or why not.


116. Is 0.10100100010000 ...a repeating decimal?
     Explain why or why not.


117. A student divided 19 by 25 to find the decimal
     equivalent of to be 0.76. Explain how she can
     check this result.


118. Explain the error in the following work to find the
     decimal equivalent for.

Thus,

REVIEW

119. Write each set of numbers.
     a. the first ten whole numbers
     b. the first ten prime numbers
     c. the integers


120. Give an example of each property.
     a. the commutative property of addition
     b. the associative property of multiplication
     c. the multiplication property of 1

5

6

1.2.

1.2

(^5)  6.0
 5
10
 10
0
5
6
19
25

0.1333

0.5

1

3

3

4

3

4