Personal Finance
Graded Assignment
Unit Test, Part 2
Show all your work.
(7 points)
1. A health department estimates that 8 vials of malaria serum will treat 100 people. At this rate, how many vials are required to treat 175 people? Write your answer as a complete sentence.
Answer:
8/100 = 0.08*175=14
So, 14 vials are required to treat 175 people.
(7 points)
2. A chemist wishes to make 3 liters of a 7% acid solution by mixing a 9% acid solution and a 4% acid solution. How many liters of each solution should the chemist use? Write your answer as a complete sentence.
Be sure to:
Define your variable and expressions for the quantities.
Write an equation that models the problem.
Solve the equation.
State the answer in a complete sentence.
Answer:
Liters
Percent Acid
Liters of Acid
7%
3
.70
2.1
9%
.4
.90
.90x
4%
X + 3
.40
.40(x + 3)
2.1 + .90x = .40(x + 3)
2.1 + .90x = .40 x+ 1.2 -.90 x -.90x
2.1 = -0.5 x + 1.2
-1.2 -1.2
.9 = -.5x
-.5 -.5
0.4 = x
(9 points)
3. Suppose you pay $24 for a pair of shoes that has been discounted 20%. What is the original price of the shoes? Show how you identify what you are looking for, set up an equation, arrive at your answer, and check your work. Then clearly state your answer.
Answer
X*.8=24
X=24/.8
X= 30 (original price)
24/x 80/100
24/80=0.3 *100 =30
Unit Test, Part 2
Show all your work.
(7 points)
1. A health department estimates that 8 vials of malaria serum will treat 100 people. At this rate, how many vials are required to treat 175 people? Write your answer as a complete sentence.
Answer:
8/100 = 0.08*175=14
So, 14 vials are required to treat 175 people.
(7 points)
2. A chemist wishes to make 3 liters of a 7% acid solution by mixing a 9% acid solution and a 4% acid solution. How many liters of each solution should the chemist use? Write your answer as a complete sentence.
Be sure to:
Define your variable and expressions for the quantities.
Write an equation that models the problem.
Solve the equation.
State the answer in a complete sentence.
Answer:
Liters
Percent Acid
Liters of Acid
7%
3
.70
2.1
9%
.4
.90
.90x
4%
X + 3
.40
.40(x + 3)
2.1 + .90x = .40(x + 3)
2.1 + .90x = .40 x+ 1.2 -.90 x -.90x
2.1 = -0.5 x + 1.2
-1.2 -1.2
.9 = -.5x
-.5 -.5
0.4 = x
(9 points)
3. Suppose you pay $24 for a pair of shoes that has been discounted 20%. What is the original price of the shoes? Show how you identify what you are looking for, set up an equation, arrive at your answer, and check your work. Then clearly state your answer.
Answer
X*.8=24
X=24/.8
X= 30 (original price)
24/x 80/100
24/80=0.3 *100 =30