Page 332 - Basic College Mathematics with Early Integers

S E C T I O N 4.3 I MULTIPLYING DECIMALS AND CIRCUMFERENCE OF A CIRCLE 309

67. Due to a higher world demand, fewer growers, and 68. For deliveries in May 2008, the price of soybeans, set at
bad weather, May 2008 prices for spring wheat rose to the Chicago Board of Trade, was $14.8425 per bushel.
a price of $12.145 per bushel, the highest ever. How How much would a company pay for 10,000 bushels of
much would 100 bushels of wheat cost at this price? soybeans? (Source: Chicago Board of Trade)
(Source: Chicago Board of Trade)

The table shows currency exchange rates for various countries in a recent month.To find the amount of foreign currency
equivalent to an amount of U.S. dollars, multiply the U.S. dollar amount by the exchange rate listed in the table. Use this
table to answer Exercises 69 through 72.

69. How many Canadian dollars are equivalent to
Foreign Currency Exchange Rates
$750 U.S.?
Country Exchange Rate
70. Suppose you wish to exchange 300 American dollars
Canadian dollar 1.182 in Chinese yuan. How much money, in Chinese yuan,
would you receive?
European Union euro 0.7428
71. The Scarpulla family is traveling to New Zealand.
New Zealand dollar 1.6252
How many New Zealand dollars can they “buy” with
Chinese yuan 6.8332
800 U.S. dollars?
Japanese yen 101.4
72. A French tourist to the United States spent $130 for
Swiss franc 1.1339 souvenirs at the Head of the Charles Regatta in
Boston. How much money did he spend in euros?
Round to the nearest cent.

Review

Divide. See Sections 1.7 and 3.3.
24 8 162 9
73. 2916 , 6 74. 2920 , 365 75. - , 76. ,-
7 21 25 75

Concept Extensions

Mixed Practice (Sections 4.2, 4.3) Perform the indicated operations.

77. 3.6 + 0.04 78. 7.2 + 0.14 + 98.6 79. 3.6 - 0.04

80. 100 - 48.6 81. -0.221 * 0.5 82. -3.6 * 0.04

83. Find how far radio waves travel in 20.6 seconds. 84. If it takes radio waves approximately 8.3 minutes to
(Radio waves travel at a speed of 1.86 * 100,000 travel from the Sun to the Earth, find approximately
miles per second.) how far it is from the Sun to the Earth. (Hint: See
Exercise 83.)

85. In your own words, explain how to find the 86. In your own words, explain how to multiply by a
number of decimal places in a product of decimal power of 10.
numbers.

87. Write down two decimal numbers whose product will contain 5 decimal places.Without multiplying, explain how
you know your answer is correct.