College Mathematics

Exercises

Section 2.1: Exercise 96 Solve each problem by writing and solving an equation.
96. World grain demand. Freeport McMoRan projects that in 2010 world grain supply will be 1.8 trillion metric tons and the supply will be only ¾ of world grain demand. What will world grain demand be in 2010?

Section 2.2: Exercise: 94 and 96 Solve each problem.(note 5/9 is a fraction I could not make the fraction symbol in excel)
94. Fahrenheit temperature. Water boils at 212°F.
a) Use the accompanying graph to determine the Celsius temperature at which water boils.
b) Find the Fahrenheit temperature of hot tap water at
70°C by solving the equation
70 = 5/9(F -32).

96. Perimeter of a triangle. The perimeter of the triangle shown in the accompanying figure is 12 meters. Determine the values of x, x =1, and x =2 by solving the equation
x=(x=1)=(x=2)=12

Section 2.3: Exercises 80, 88, and 94 Solve each equation.
80. -3 -4(t -5)=-2(t =3) + 11
88. 0.08x + 0.5(x +100) =73.2
94. Raising rabbits. Before Roland sold two female rabbits, half of his rabbits were female. After the sale, only one third of his rabbits were female. If x represents his original number of rabbits, then

1/2x-2=1/3(x-2)

Solve this equation to find the number of rabbits that he had before the sale.
Section 2.4: Exercises 98
98. Cowling's rule. Cowling's rule is another method for determining the dosage of a drug to prescribe to a child. For this rule, the formula
d=D(a+1)/24 (note this is a fraction problem Please convert the problem and answer I could not so it in word. D(a=1) is over 24
gives the child's dosage d, where D is the adult dosage and a is the age of the child in years. If the adult dosage of a drug is 600 milligrams and a doctor uses this formula to determine that a child's dosage is 200 milligrams, then how old is the child?

Section 2.5: Exercises 36, 48, 58, and 68
Write algebraic expressions for the following unknown integers.
36. Three consecutive even integers

Find an algebraic expression for the quantity in italics using the given information
48. The rate, given that the distance is 200 feet and the time is x +3 seconds

58. The perimeter of a rectangle, given that the length is x yards and the width is 10 yards shorter

Identify the variable and write an equation that describes each situation
68. Gwen sold her car on consignment for x dollars. The saleswoman's commission was 10% of the selling price and Gwen received $6570.

Section 2.6: Exercise 14
14. Consecutive even integers. Find four consecutive even integers whose sum is 340.

Section 2.7: Exercises 10, 14, and 18
Show a complete solution to each problem.
10. Chrysler Sebring. After getting a 15% discount on the price of a new Chrysler Sebring convertible, Helen paid $27,000. What was the original price of the convertible to the nearest dollar?
14. Toyota Corolla. Gwen bought a new Toyota Corolla. The selling price plus the 8% state sales tax was $15,714. What was the selling price?

18. High-risk funds. Of the $50,000 that Natasha pocketed on her last real estate deal, $20,000 went to charity. She invested part of the remainder in Dreyfus New Leaders Fund with an annual yield of 16% and the rest in Templeton Growth Fund with an annual yield of 25%. If she made $6060 on these investments in 1 year, then how much did she invest in each fund?

Section 2.8: Exercise 88 Write an inequality to describe each situation.
88. Building a ski ramp. Write an inequality in the variable x for the degree measure of the smallest angle of the triangle shown in the figure, given that the degree measure of the smallest angle is at most 30°.