Basic Mathematics for College Students

APPLICATIONS

Use signed numbers to solve each problem.

83. RECORD TEMPERATURES The lowest recorded
    temperatures for Michigan and Minnesota are shown
    below. Use the given information to find the highest
    recorded temperature for each state.
    87. FLOODING After a heavy rainstorm, a river that
    had been 9 feet under flood stage rose 11 feet in
    a 48-hour period.
    a. Represent that level of the river before the storm
    using a signed number.
    b. Find the height of the river after the storm in
    comparison to flood stage.
    88. ATOMS An atom is composed of protons, neutrons,
    and electrons. A proton has a positive charge
    (represented by ), a neutron has no charge, and an
    electron has a negative charge. Two simple
    models of atoms are shown below.
    a. How many protons does the atom in figure (a)
    have? How many electrons?
    b. What is the net charge of the atom in figure (a)?
    c. How many protons does the atom in figure (b)
    have? How many electrons?
    d. What is the net charge of the atom in figure (b)?
    89. CHEMISTRY The three steps of a chemistry lab
    experiment are listed here. The experiment begins
    with a compound that is stored at.
    Step 1Raise the temperature of the
    compound 200°.
    Step 2Add sulfur and then raise the
    temperature 10°.
    Step 3Add 10 milliliters of water, stir,
    and raise the temperature 25°.
    What is the resulting temperature of the mixture after
    step 3?

40°F

(a) (b)

Electron

Proton

(1)

 1

154 Chapter 2 The Integers

fromCampus to Careers

Personal Financial Advisor

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90. Suppose as a personal
    financial advisor, your clients
    are considering purchasing
    income property. You find a
    duplex apartment unit that
    is for sale and learn that the
    maintenance costs, utilities,
    and taxes on it total $900
    per month. If the current
    owner receives monthly
    rental payments of $450 and $380 from the tenants,
    does the duplex produce a positive cash flow each
    month?

Lowest Highest

State temperature temperature

Michigan

Minnesota July 6, 1936: 174°F warmer

than the record low

Feb. 2, 1996:

60°F

July 13, 1936: 163°F warmer

than the record low

Feb. 9, 1934:

51°F

(Source:The World Almanac Book of Facts,2009)

84. ELEVATIONS The lowest point in the United
    States is Death Valley, California, with an elevation of
    feet (282 feet below sea level). Mt. McKinley
    (Alaska) is the highest point in the United States. Its
    elevation is 20,602 feet higher than Death Valley.
    What is the elevation of Mt. McKinley? (Source:The
    World Almanac Book of Facts,2009)


85. SUNKEN SHIPS Refer to the map below.
    a. The German battleship Bismarck,one of the
    most feared warships of World War II, was sunk
    by the British in 1941. It lies on the ocean floor
    15,720 feet below sea level off the west coast of
    France. Represent that depth using a signed
    number.
    b. In 1912, the famous cruise ship Titanicsank after
    striking an iceberg. It lies on the North Atlantic
    ocean floor, 3,220 feet higher than the Bismarck.
    At what depth is the Titanicresting?


86. JOGGING A businessman’s lunchtime workout
    includes jogging up ten stories of stairs in his high-rise
    office building. He starts the workout on the fourth
    level below ground in the underground parking
    garage.
    a. Represent that level using a signed number.
    b. On what story of the building will he finish his
    workout?

Titanic

Bismarck

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