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Mathematics LibreTexts

5.5: Unit Conversion - American System

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    31019
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    In this section we will develop a technique for converting units used in the American system. We begin with a discussion of common measurements of length in the United States.

    Units of Length

    The most common units of length are the inch, foot, yard, and mile. Our focus will be on the technique used to convert from one unit of length to another.

    American Units of Length

    Facts relating common units of length.

    • 1 foot (ft) = 12 inches (in)
    • 1 yard (yd) = 3 feet (ft)
    • 1 mile (mi) = 5280 feet (ft)

    Take for example, the fact that there are 3 feet in 1 yard, which can be stated as an equation, using the common abbreviations for feet (ft) and yards (yd).

    3 ft = 1 yd

    If we divide both sides of the equation by 3 ft,

    \[ \frac{3 \text{ ft}}{3 \text{ ft}} = \frac{1 \text{ yd}}{3 \text{ ft}}, \nonumber\nonumber \]

    or equivalently,

    \[1 = \frac{1 \text{ yd}}{3 \text{ ft}}. \nonumber\nonumber \]

    The key observation is the fact that the ratio 1 yd/3 ft equals the number 1. Consequently, multiplying by the “conversion factor” 1 yd/3 ft is equivalent to multiplying by 1. This can be used to change a measurement in feet to yards.

    Example 1

    Change 36 feet to yards.

    Solution

    Multiply by the conversion factor 1 yd/3 ft.

    \[ \begin{aligned} 36 \text{ ft} = 36 \text{ ft} \cdot 1 ~ & \textcolor{red}{ \text{ Multiplicative Identity Property.}} \\ = 36 \text{ ft} \cdot \frac{1 \text{ yd}}{3 \text{ ft}} ~ & \textcolor{red}{ \text{ Replace 1 with 1 yd/3 ft.}} \\ = 36 \cancel{ \text{ ft}} \cdot \frac{1 \text{ yd}}{3 \cancel{ \text{ ft}}} ~ & \textcolor{red}{ \text{ Cancel common unit.}} \\ = \frac{36 \cdot 1}{3} \text{ yd} ~ & \textcolor{red}{ \text{ Multiply fractions.}} \\ = \frac{36}{3} \text{ yd} ~ & \textcolor{red}{ \text{ Simplify.}} \\ = 12 \text{ yd} ~ & \textcolor{red}{ \text{ Divide.}} \end{aligned}\nonumber \]

    Hence, 36 feet equals 12 yards.

    Exercise

    Change 81 feet to yards.

    Answer

    27 yards

    On the other hand, we can start again with

    \[3 \text{ ft} = 1 \text{ yd}\nonumber \]

    and divide both sides of the equation by 1 yd.

    \[\frac{3 \text{ ft}}{1 \text{ yd}} = \frac{1 \text{ yd}}{1 \text{ yd}} \nonumber\nonumber \]

    This gives the conversion factor

    \[ \frac{3 \text{ ft}}{1 \text{ yd}} = 1.\nonumber\nonumber \]

    The key observation is the fact that the ratio 3 ft/1 yd equals the number 1. Consequently, multiplying by the “conversion factor” 3 ft/1 yd is equivalent to multiplying by 1. This can be used to change a measurement in yards to feet.

    Example 2

    Change 18 yards to feet.

    Solution

    Multiply by the conversion factor 3 ft/1 yd.

    \[ \begin{aligned} 18 \text{ yd} = 18 \text{ yd} \cdot 1 ~ & \textcolor{red}{ \text{ Multiplicative Identity Property.}} \\ = 18 \text{ yd} \cdot \frac{1 \text{ ft}}{1 \text{ yd}} ~ & \textcolor{red}{ \text{ Replace 1 with 3 ft/1 yd.} \\ = 18 \cancel{ \text{ yd}} \cdot \frac{3 \text{ ft}}{1 \cancel{ \text{ yd}} ~ & \textcolor{red}{ \text{ Cancel common unit.}} \\ = \frac{18 \cdot 3}{1} \text{ ft} ~ & \textcolor{red}{ \text{ Multiply fractions.}} \\ = 54 \text{ ft} ~ & \textcolor{red}{ \text{ Simplify.}} \end{aligned}\nonumber \]

    Hence, 18 yards equals 54 feet.

    Exercise

    Change 15 yards to feet.

    Answer

    45 feet

    Another common comparison is the fact that there are 12 inches in 1 foot. This can be represented as an equation using the common abbreviation for inches (in) and feet (ft).

    \[12 \text{ in} = 1 \text{ ft}\nonumber \]

    Dividing both sides by 12 in

    \[ \frac{12 \text{ in}}{12 \text{ in}} = \frac{1 \text{ ft}}{12 \text{ in}},\nonumber \]

    yields the conversion factor

    \[1 = \frac{1 \text{ ft}}{12 \text{ in}}.\nonumber \]

    The key observation is the fact that the ratio 1 ft/12 in equals the number 1. Consequently, multiplying by the “conversion factor” 1 ft/12 in is equivalent to multiplying by 1. This can be used to change a measurement in inches to feet.

    Example 3

    Change 24 inches to feet.

    Solution

    Multiply by the conversion factor 1 ft/12 in.

    \[ \begin{aligned} 24 \text{ in} = 24 \text{ in} \cdot 1 ~ & \textcolor{red}{ \text{ Multiplicative Identity Property.}} \\ = 24 \text{ in} \cdot \frac{1 \text{ ft}}{12 \text{ in}} ~ & \textcolor{red}{ \text{ Replace 1 with 1 ft/12 in.}} \\ = 24 \cancel{ \text{ in}} \cdot \frac{1 \text{ in}}{12 \cancel{ \text{ in}}} ~ & \textcolor{red}{ \text{ Cancel common unit.}} \\ = \frac{24 \cdot 1}{12} \text{ ft} ~ & \textcolor{red}{ \text{ Multiply fractions.}} \\ = 2 \text{ ft} ~ & \textcolor{red}{ \text{ Simplify.}} \end{aligned}\nonumber \]

    Hence, 24 inches equals 2 feet.

    Exercise

    Change 48 inches to feet.

    Answer

    4 feet

    We provide a summary of conversion factors for units of length in Table 6.1.

    Table 6.1: Conversion factors for units of length.
    Convert Conversion Factor Convert Conversion Factor
    feet to inches 12 in/1 ft inches to feet 1 ft/12 in
    yards to feet 3 ft/1 yd feet to yards 1 yd/3 ft
    miles to feet 5280 ft/1 mi feet to miles 1 mi/5280 ft

    Some conversions require more than one application of a conversion factor.

    Example 4

    Change 4 yards to inches.

    Solution

    We multiply by a chain of conversion factors, the first to change yards to feet, the second to change feet to inches.

    \[ \begin{aligned} 4 \text{ yd} = 4 \text{ yd} \cdot \frac{3 \text{ ft}}{1 \text{ yd}} \cdot \frac{12 \text{ in}}{1 \text{ ft}} ~ & \textcolor{red}{ \text{ Multiply by conversion factors.}} \\ = 4 \cancel{ \text{ yd}} \cdot \frac{3 \cancel{ \text{ ft}}{1 \cancel{ \text{ yd}} \cdot \frac{12 \text{ in}}{1 \cancel{ \text{ ft}}} ~ & \textcolor{red}{ \text{ Cancel common units.}} \\ = \frac{4 \cdot 3 \cdot 12}{1 \cdot 1} \text{ in} ~ & \textcolor{red}{ \text{ Multiply fractions.}} \\ = 144 \text{ in} ~ & \textcolor{red}{ \text{ Simplify.}} \end{aligned}\nonumber \]

    Hence, 4 yards equals 144 inches.

    Exercise

    Change 8 yards to inches.

    Answer

    288 inches

    Example 5

    Change 2 miles to yards.

    Solution

    We multiply by a chain of conversion factors, the first to change miles to feet, the second to change feet to yards.

    \[ \begin{aligned} 2 \text{ mi} = 2 \text{ mi} \cdot \frac{5280 \text{ ft}}{1 \text{ mi}} \cdot \frac{1 \text{ yd}}{3 \text{ ft}} ~ & \textcolor{red}{ \text{ Multiply by conversion factors.}} \\ = 2 \cancel{ \text{ mi}} \cdot \frac{5280 \cancel{ \text{ ft}}}{1 \cancel{ \text{ mi}}} \cdot \frac{1 \text{ yd}}{3 \cancel{ \text{ ft}}} ~ & \textcolor{red}{ \text{ Cancel common units.}} \\ = \frac{2 \cdot 5280 \cdot 1}{1 \cdot 3} \text{ yd} ~ & \textcolor{red}{ \text{ Multiply fractions.}} \\ = 3520 \text{ yd} ~ & \textcolor{red}{ \text{ Simplify.}} \end{aligned}\nonumber \]

    Hence, 2 miles equals 3,520 yards.

    Exercise

    Change 5 miles to yards.

    Answer

    8,800 yards

    Units of Weight

    The most common units of weight are the ounce, pound, and ton. Our focus will remain on how to convert from one unit to another.

    American Units of Weight

    Facts relating common units of weight.

    • 1 pound (lb) = 16 ounces (oz)
    • 1 ton = 2000 pounds (lb)

    The above facts lead to the conversion factors in Table 6.2.

    Table 6.2: Conversion factors for units of weight.
    Convert Conversion Factor Convert Conversion Factor
    pounds to ounces 16 oz/1 lb ounces to pounds 1 lb/16 oz
    tons to pounds 2000 lb/1 ton pounds to tons 1 ton/2000 lb

    Example 6

    Change \(2 \frac{1}{2}\) pounds to ounces.

    Solution

    Multiply by the appropriate conversion factor.

    \[ \begin{aligned} 2 \frac{1}{2} \text{ lb} = 2 \frac{1}{2} \text{ lb} \cdot \frac{16 \text{ oz}}{1 \text{ lb}} ~ & \textcolor{red}{ \text{ Multiply by conversion factor.}} \\ = 2 \frac{1}{2} \cancel{ \text{ lb}} \cdot \frac{16 \text{ oz}}{1 \cancel{ \text{ lb}}} ~ & \textcolor{red}{ \text{ Cancel common units.}} \\ = \left( 2 \frac{1}{2} \cdot 16 \right) \text{ oz } & \textcolor{red}{ \text{ Multiply fractions.}} \\ = \left( \frac{5}{2} \cdot 16 \right) \text{ oz } & \textcolor{red}{ \text{ Mixed to improper fraction.}} \\ = \frac{80}{2} \text{ oz } & \textcolor{red}{ \text{ Multiply.}} \\ = 40 \text{ oz } & \textcolor{red}{ \text{ Divide.}} \end{aligned}\nonumber \]

    Hence, \(2 \frac{1}{2}\) pounds equals 40 ounces.

    Exercise

    Change \(6 \frac{1}{4}\) pounds to ounces.

    Answer

    100 ounces

    Example 7

    Change 3.2 tons to ounces.

    Solution

    This exercise requires multiplying by a chain of conversion factors.

    \[ \begin{aligned} 3.2 \text{ ton } = 3.2 \text{ ton } \cdot \frac{2000 \text{ lb}}{1 \text{ ton}} \cdot \frac{16 \text{ oz}}{1 \text{ lb}} ~ & \textcolor{red}{ \text{ Multiply by conversion factors.}} \\ = 3.2 \cancel{ \text{ ton}} \cdot \frac{2000 \cancel{ \text{ lb}}}{1 \cancel{ \text{ ton}}} \cdot \frac{16 \text{ oz}}{1 \cancel{ \text{ lb}}} ~ & \textcolor{red}{ \text{ Cancel common units.}} \\ = \frac{3.2 \cdot 2000 \cdot 16}{1 \cdot 1} \text{ oz } & \textcolor{red}{ \text{ Multiply fractions.}} \\ = 102,400 \text{ oz } & \textcolor{red}{ \text{ Simplify.}} \end{aligned}\nonumber \]

    Hence, 3.2 tons equals 102,400 ounces.

    Exercise

    Change 4.1 tons to ounces.

    Answer

    128,000 ounces

    Units of Volume

    The most common units of volume are fluid ounces, cups, pints, quarts, and gallons. We will focus on converting from one unit to another.

    American Units of Volume

    Facts relating common units of volume.

    • 1 cup (c) = 8 fluid ounces (fl oz)
    • 1 pint (pt) = 2 cups (c)
    • 1 quart (qt) = 2 pints (pt)
    • 1 gallon (gal) = 4 quarts (qt)

    These facts lead to the conversion factors listed in Table 6.3.

    Table 6.3: Conversion factors for units of volume.
    Convert Conversion Factor Convert Conversion Factor
    cups to ounces 8 fl oz/1 c ounces to cups 1c/8 fl oz
    pints to cups 2 c/1 pt cups to pints 1 pt/2 c
    quarts to pints 2 pt/1 qt pints to quarts 1 qt/2 pt
    gallons to quarts 4 qt/1 gal quarts to gallons 1 gal/4 qt

    Example 8

    Change 5.6 gallons to pints.

    Solution

    This exercise requires multiplying by a chain of conversion factors.

    \[ \begin{aligned} 5.6 \text{ gal } = 5.6 \text{ gal } \cdot \frac{4 \text{ qt}}{1 \text{ gal}} \cdot \frac{2 \text{ pt}}{1 \text{ qt}} ~ & \textcolor{red}{ \text{ Multiply by conversion factors.}} \\ = 5.6 \cancel{\text{ gal }} \cdot \frac{4 \cancel{\text{ qt}}}{1 \cancel{ \text{ gal}}} \cdot \frac{2 \text{ pt}}{1 \cancel{ \text{ qt}}} ~ & \textcolor{red}{ \text{ Cancel common units.}} \\ = \frac{5.6 \cdot 4 \cdot 2}{1 \cdot 1} \text{ pt } & \textcolor{red}{ \text{ Multiply fractions.}} \\ = 44.8 \text{ pt } & \textcolor{red}{ \text{ Simplify.}} \end{aligned}\nonumber \]

    Hence, 5.6 gallons equals 44.8 pints.

    Exercise

    Change 3.2 gallons to pints.

    Answer

    25.6 pints

    Units of Time

    The most common units of time are seconds, minutes, hours, days, and years.

    American Units of Time

    Facts relating common units of time.

    • 1 minute (min) = 60 seconds (s)
    • 1 hour (hr) = 60 minutes (min)
    • 1 day (day) = 24 hours (hr)
    • 1 year (yr) = 365 days (day)

    These facts lead to the conversion factors in Table 6.4.

    Table 6.4: Conversion factors for units of time.
    Convert Conversion Factor Convert Conversion Factor
    minutes to seconds 60 s/1 min seconds to minutes 1 min/60 s
    hours to minutes 60 min/1 hr minutes to hours 1 hr/60 min
    days to hours 24 hr/1 day hours to days 1 day/24 hr
    years to days 365 day/1 yr days to years 1 yr/365 day

    Example 9

    How many seconds in a year?

    Solution

    A chain of conversion factors is needed.

    \[ \begin{aligned} 1 \text{ yr } = 1 \text{ yr } \cdot \frac{365 \text{ day}}{1 \text{ yr}} \cdot \frac{24 \text{ hr}}{1 \text{ day}} \cdot \frac{60 \text{ min}}{1 \text{ hr}} \cdot \frac{60 \text{ s}}{1 \text{ min}} ~ & \textcolor{red}{ \text{ Conversion factors.}} \\ = 1 \cancel{ \text{ yr}} \cdot \frac{365 \cancel{ \text{ day}}}{1 \cancel{ \text{ yr}}} \cdot \frac{24 \cancel{ \text{ hr}}}{1 \cancel{ \text{ day}}} \cdot \frac{60 \cancel{ \text{ min}}}{1 \cancel{ \text{ hr}}} \cdot \frac{60 \text{ s}}{1 \cancel{ \text{ min}}} & \textcolor{red}{ \text{ Cancel common units.}} \\ = \frac{1 \cdot 365 \cdot 24 \cdot 60 \cdot 60}{1 \cdot 1 \cdot 1 \cdot 1} \text{ s } & \textcolor{red}{ \text{ Multiply fractions.}} \\ = 31,536,000 \text{ s } & \textcolor{red}{ \text{ Simplify.}} \end{aligned}\nonumber \]

    Thus, 1 year equals 31,536,000 seconds.

    Exercise

    How many seconds in a day?

    Answer

    86,400 seconds

    Converting Units of Speed

    Ever wonder how fast a baseball is moving?

    Example 10

    A professional pitcher can throw a baseball at 95 miles per hour. How fast is this in feet per second? Round your answer to the nearest foot per second.

    Solution

    There are 5280 feet in a mile, 60 minutes in an hour, and 60 seconds in a minute.

    \[ \begin{aligned} 95 \frac{ \text{mi}}{ \text{h}} \approx 95 \frac{ \text{mi}}{\text{h}} \cdot \frac{5280 \text{ ft}}{1 \text{ mi}} \cdot \frac{1 \text{ h}}{60 \text{ min}} \cdot \frac{1 \text{ min}}{60 \text{ s}} ~ & \textcolor{red}{ \text{ Conversion factors.}} \\ \approx 95 \frac{ \cancel{\text{mi}}}{\cancel{\text{h}}} \cdot \frac{5280 \text{ ft}}{1 \cancel{\text{ mi}}} \cdot \frac{1 \cancel{\text{ h}}}{60 \cancel{\text{ min}}} \cdot \frac{1 \cancel{\text{ min}}}{60 \text{ s}} ~ & \textcolor{red}{ \text{ Cancel common units.}} \\ \approx \frac{95 \cdot 5280 \cdot 1 \cdot 1}{1 \cdot 60 \cdot 60} \frac{ \text{ft}}{\text{s}} ~ & \textcolor{red}{ \text{ Multiply fractions.}} \\ \approx 139.3 \frac{ \text{ft}}{\text{s}} ~ & \textcolor{red}{ \text{ Multiply and divide.}} \end{aligned}\nonumber \]

    To round to the nearest foot per second, identify the rounding and test digits.

    Screen Shot 2019-09-20 at 12.42.19 PM.png

    Because the test digit is less than 5, leave the rounding digit alone and truncate. Thus, to the nearest foot per second, the speed is approximately 139 feet per second.

    Whew! Since the batter stands at home plate, which is about 60 feet from where the pitch is delivered, the batter has less than 1/2 a second to react to the pitch!

    Exercise

    A women’s softball pitcher can throw her fastball at 60 miles per hour. How fast is this in feet per second? Round your answer to the nearest foot per second.

    Answer

    88 feet per second

    Exercises

    1. Change 8 yards to feet.

    2. Change 60 yards to feet.

    3. Change 261 feet to yards.

    4. Change 126 feet to yards.

    5. Change 235 inches to yards. Round your answer to the nearest tenth of a yard.

    6. Change 244 inches to yards. Round your answer to the nearest tenth of a yard.

    7. Change 141 feet to yards.

    8. Change 78 feet to yards.

    9. Change 2.8 miles to feet.

    10. Change 4.9 miles to feet.

    11. Change 104 inches to yards. Round your answer to the nearest tenth of a yard.

    12. Change 101 inches to yards. Round your answer to the nearest tenth of a yard.

    13. Change 168,372 inches to miles, correct to the nearest tenth of a mile.

    14. Change 198,550 inches to miles, correct to the nearest tenth of a mile.

    15. Change 82 feet to inches.

    16. Change 80 feet to inches.

    17. Change 2.9 yards to inches. Round your answer to the nearest inch.

    18. Change 4.5 yards to inches. Round your answer to the nearest inch.

    19. Change 25,756 feet to miles. Round your answer to the nearest tenth of a mile.

    20. Change 19,257 feet to miles. Round your answer to the nearest tenth of a mile.

    21. Change 5 yards to feet.

    22. Change 20 yards to feet.

    23. Change 169,312 inches to miles, correct to the nearest tenth of a mile.

    24. Change 162,211 inches to miles, correct to the nearest tenth of a mile.

    25. Change 1.5 yards to inches. Round your answer to the nearest inch.

    26. Change 2.1 yards to inches. Round your answer to the nearest inch.

    27. Change 360 inches to feet.

    28. Change 768 inches to feet.

    29. Change 48 inches to feet.

    30. Change 528 inches to feet.

    31. Change 15,363 feet to miles. Round your answer to the nearest tenth of a mile.

    32. Change 8,540 feet to miles. Round your answer to the nearest tenth of a mile.

    33. Change 1.7 miles to inches.

    34. Change 4.7 miles to inches.

    35. Change 3.1 miles to inches.

    36. Change 1.8 miles to inches.

    37. Change 3.6 miles to feet.

    38. Change 3.1 miles to feet.

    39. Change 18 feet to inches.

    40. Change 33 feet to inches.


    41. Change \(5 \frac{1}{8}\) pounds to ounces.

    42. Change \(3 \frac{1}{16}\) pounds to ounces.

    43. Change 2.4 tons to ounces.

    44. Change 3.4 tons to ounces.

    45. Change 34 ounces to pounds. Express your answer as a fraction reduced to lowest terms.

    46. Change 78 ounces to pounds. Express your answer as a fraction reduced to lowest terms.

    47. Change 2.2 tons to pounds.

    48. Change 4.8 tons to pounds.

    49. Change 70 ounces to pounds. Express your answer as a fraction reduced to lowest terms.

    50. Change 20 ounces to pounds. Express your answer as a fraction reduced to lowest terms.

    51. Change 9,560 pounds to tons. Round your answer to the nearest tenth of a ton.

    52. Change 9,499 pounds to tons. Round your answer to the nearest tenth of a ton.

    53. Change \(2 \frac{1}{2}\) pounds to ounces.

    54. Change \(7 \frac{1}{16}\) pounds to ounces.

    55. Change 5.9 tons to pounds.

    56. Change 2.1 tons to pounds.

    57. Change 2.5 tons to ounces.

    58. Change 5.3 tons to ounces.

    59. Change 8,111 pounds to tons. Round your answer to the nearest tenth of a ton.

    60. Change 8,273 pounds to tons. Round your answer to the nearest tenth of a ton.


    61. Change 4.5625 pints to fluid ounces.

    62. Change 2.9375 pints to fluid ounces.

    63. Change 32 fluid ounces to pints.

    64. Change 160 fluid ounces to pints.

    65. Change 3.7 gallons to pints.

    66. Change 2.4 gallons to pints.

    67. Change 216 pints to gallons.

    68. Change 96 pints to gallons.

    69. Change 544 fluid ounces to pints.

    70. Change 432 fluid ounces to pints.

    71. Change 112 pints to gallons.

    72. Change 200 pints to gallons.

    73. Change 7.7 gallons to pints.

    74. Change 5.7 gallons to pints.

    75. Change 3.875 pints to fluid ounces.

    76. Change 3 pints to fluid ounces.


    77. Change 7.8 years to hours.

    78. Change 4.7 years to hours.

    79. Change 7.6 years to hours.

    80. Change 6.6 years to hours.

    81. Change 4,025,005 seconds to days. Round your answer to the nearest tenth of a day.

    82. Change 4,672,133 seconds to days. Round your answer to the nearest tenth of a day.

    83. Change 37,668 hours to years.

    84. Change 40,296 hours to years.

    85. Change 22,776 hours to years.

    86. Change 29,784 hours to years.

    87. Change 96 days to seconds.

    88. Change 50 days to seconds.

    89. Change 40 days to seconds.

    90. Change 10 days to seconds.

    91. Change 3,750,580 seconds to days. Round your answer to the nearest tenth of a day.

    92. Change 4,493,469 seconds to days. Round your answer to the nearest tenth of a day.


    93. Change 367 feet per second to miles per hour. Round your answer to the nearest mile per hour.

    94. Change 354 feet per second to miles per hour. Round your answer to the nearest mile per hour.

    95. Change 442 feet per second to miles per hour. Round your answer to the nearest mile per hour.

    96. Change 388 feet per second to miles per hour. Round your answer to the nearest mile per hour.

    97. Change 30 miles per hour to feet per second. Round your answer to the nearest foot per second.

    98. Change 99 miles per hour to feet per second. Round your answer to the nearest foot per second.

    99. Change 106 miles per hour to feet per second. Round your answer to the nearest foot per second.

    100. Change 119 miles per hour to feet per second. Round your answer to the nearest foot per second.


    101. Strong man. Famed strongman Joe Rollino, who was still bending quarters with his fingers at age 104, once lifted 3, 200 pounds at Coney Island Amusement Park. How many tons did Joe lift that day? Associated Press-Times-Standard 01/12/10 NYC amusement park strongman, 104, killed by van.

    102. Earth day. The amount of time it takes the Earth to rotate once around its axis is one day. How many seconds is that?

    103. Water break. “The average age of Washington, DC’s water pipes is 76 years, and they are not alone. Every two minutes, somewhere in the country, a pipe breaks.” How many pipes break each year in the US? New York Times 03/14/10 Saving U.S. water and sewer systems could be costly.


    Answers

    1. 24 feet

    3. 87 yards

    5. 6.5 yards

    7. 47 yards

    9. 14,784 feet

    11. 2.9 yards

    13. 2.7 miles

    15. 984 inches

    17. 104 inches

    19. 4.9 miles

    21. 15 feet

    23. 2.7 miles

    25. 54 inches

    27. 30 feet

    29. 4 feet

    31. 2.9 miles

    33. 107,712 inches

    35. 196,416 inches

    37. 19,008 feet

    39. 216 inches

    41. 82 ounces

    43. 76,800 ounces

    45. \(2 \frac{1}{8}\) pounds

    47. 4,400 pounds

    49. \(4 \frac{3}{8}\) pounds

    51. 4.8 tons

    53. 40 ounces

    55. 11,800 pounds

    57. 80,000 ounces

    59. 4.1 tons

    61. 73 fluid ounces

    63. 2 pints

    65. 29.6 pints

    67. 27 gallons

    69. 34 pints

    71. 14 gallons

    73. 61.6 pints

    75. 62 fluid ounces

    77. 68,328 hours

    79. 66,576 hours

    81. 46.6 days

    83. 4.3 years

    85. 2.6 years

    87. 8,294,400 seconds

    89. 3,456,000 seconds

    91. 43.4 days

    93. 250 mi/hr

    95. 301 mi/hr

    97. 44 ft/s

    99. 155 ft/s

    101. 1.6 tons

    103. 262, 800