1Math 50 : Elementary Algebra

Prepare for the final exam.

1.

Solve:

2.

18 is 72% of what number?

Set up the equation:

3.

Solve and graph the solution set of .

4.

Solve and graph the solution set of .

5.

Solve .

6.

Use the roster method to list the set of positive integers that are solutions of

.

7.

Solve .

8.

An adult and a child are on a see-saw 14 ft long. The adult weighs 175 lb and

the child weighs 70 lb. How many feet from the adult must the fulcrum be

placed so that the see-saw balances? (Equation: )

9.

A manufacturing engineering determines that the cost per unit for a compact

disc is $3.35 and that the fixed cost is $6180. The selling price for the

compact disc is $8.50. Find the break-even point. (Break-even means your

cost and your revenue are the same. Use the equation: Px = Cx + F)

10.

The pressure that a certain depth in the ocean can be approximated by the

equation , where P is the pressure in pounds per square inch,

and D is the depth in feet. Find the depth of a diver when the pressure on the

diver is 45 lb/sq.in.

11.

If , evaluate . (First solve for a, then evaluate.)

12.

To receive a B grade in a history course, a student must correctly answer 75

of the 90 questions on an exam. What percent of the questions must a student

answer correctly to receive a B grade? (Give the exact percent in fraction

form.)

13.

Translate into a variable expression. [Do not simply.]

(a)

the sum of a number divided by two and the number.

(b)

three less than the sum of a number and ten.

(c)

three-fourths of the sum of sixteen times a number and four.

1 Spring 2011