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MTH0011B |Math Foundations II | Unit 2 Answer Key| Ratio, Proportion, and Probability
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Date:
Answer Key
Unit 2 Assignment
Award points for answers as shown below. Starter feedback for correct and incorrect answers is in red. Use or adapt
the feedback in this Answer Key as you grade each student paper. If you have suggestions for improving this key, send
them to [email protected].
(1 point)
1. Choose the fraction in simplest form that correctly expresses this ratio. 27 to 54
1
2
1
4
1
3
Answer:
1
2
(1 point)
2. Find the unit rate of 500 miles per 25 gallons.
Answer: 20 miles per gallon
(1 point)
3. Find the unit rate of 4000 people per 80 square miles.
Answer: 50 people per mile
(1 point)
4.
5
x
x=

4 20
Answer: 25
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MTH0011B |Math Foundations II | Unit 2 Answer Key| Ratio, Proportion, and Probability
(1 point)
5.
2a
5
a=

8
10
Answer: 2
(1 point)
6. A jack for a car requires a force of 120 lbs to lift a 3,000 lb car. What is the ratio of the car's weight to the
force required to lift the car? Write the ratio in simplest form.
1
Answer: 1 to 25 or 1:25 or 25
(1 point)
7. A 17 minute telephone call from Boston to Chicago costs $2.38. What is the cost per minute?
Answer: $0.14
(1 point)
8. You would burn about 200 calories by walking for 60 minutes. About how many calories would you burn if
you walk for 15 minutes?
Answer: 50 calories
(1 point)
9. The cost of printing the football rosters for the games was 25 for $4.00. What is the cost per copy?
Answer: $0.16
(1 point)
10. Carol drove 720 km in 9 hours. What was her rate in km/hr?
Answer: 80 km per hour
(1 point)
11. Which is a better buy on apples?
5 pounds for $5.25
10 pounds for $10.25
Answer: 10 pounds for $10.25
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MTH0011B |Math Foundations II | Unit 2 Answer Key| Ratio, Proportion, and Probability
(1 point)
12. How long would the processing take to develop 1000 negatives if it takes 5 minutes to develop 100
negatives?
Answer: 50 minutes
(1 point)
13. Which is the better buy on strawberries?
2 baskets for $1.48
3 baskets for $2.07
Answer: 3 baskets for $2.07
(1 point)
14. The planet Mercury travels 180,600 miles in its orbit during the 7 hours that make up a typical school day.
Find the unit rate.
Answer: 25,800 miles per hour
(1 point)
15. Some jobs pay hourly wages; other jobs pay a salary for a week's work. One job pays $7.00 per hour of
work. A second job pays $320.00 for 40 hours of work each week. Which job pays a higher unit rate?
$7.00 per hour of work
$320 per 40 hours of work
Answer: $320 per 40 hours of work
(1 point)
16. Bananas are on sale at 8 for $.96. Find the cost of 1 banana.
Answer: $0.12
(1 point)
17. Write .7 in percent form.
Answer: 70%
(1 point)
18. Write .04 in percent form.
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MTH0011B |Math Foundations II | Unit 2 Answer Key| Ratio, Proportion, and Probability
Answer: 4%
(1 point)
19. Write 42% in decimal form.
Answer: 0.42
(1 point)
20. Write 160% in decimal form.
Answer: 1.6 or 1.60
(1 point)
21. Reduce
5
to its lowest terms.
200
1
Answer: 40
(1 point)
22. Write
1
in percent form.
20
Answer: 5%
(1 point)
23. 10% of 50 is what number?
Answer: 5
(1 point)
24. What percent of 64 is 32?
Answer: 50%
(1 point)
25. Find the percent of increase rounded to the nearest tenth. 45 to 65
Answer: 44.4%
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MTH0011B |Math Foundations II | Unit 2 Answer Key| Ratio, Proportion, and Probability
(1 point)
26. Find the percent of decrease rounded to the nearest tenth. 140 to 80
Answer: 42.9%
(1 point)
27. The membership in the pep club at the high school went from 256 to 288. What was the percent of
increase?
Answer: 12.5%
(1 point)
28. What is the sales tax for an item that costs $26.50 and has a sales tax rate of 6%?
Answer: $1.59
(1 point)
29. What is the total cost for an item that costs $140.00 and has a sales tax rate of 7.5%?
Answer: $150.50
(1 point)
30. Last year, Scott earned $5.00 per hour working at the pet store. He now earns $6.50 per hour. What is his
percent of increase?
Answer: 30%
(1 point)
31. What is 15% of 90?
Answer: 13.5
(1 point)
32. What is 33% of 130?
Answer: 42.9
(1 point)
33. A science class has 12 boys and 15 girls. What is the probability that a student chosen at random is a
boy?
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MTH0011B |Math Foundations II | Unit 2 Answer Key| Ratio, Proportion, and Probability
4
9
1
12
5
9
Answer:
4
9
(1 point)
34. Ten thousand programs are printed for the basketball game. Only one displays the winning number. What
is the probability that you will get the winning number if you purchase only one program?
Answer: 1 in 10,000 or 0.0001 or 0.01%
(1 point)
35. Ten thousand programs are printed for the basketball game. Only one displays the winning number. What
is the probability that you will not get the winning number if you purchase only one program?
Answer: 9,999 in 10,000 or 0.9999 or 99.99%
(1 point)
36. A spinner lettered A through Z is spun. What is the probability that on the first spin the spinner will land on
the first letter in your name?
1
8
1
12
1
26
Answer:
1
26
(1 point)
37. A bag contains 5 red marbles, 7 green marbles, and 3 orange marbles. Find the probability of drawing a
red marble.
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MTH0011B |Math Foundations II | Unit 2 Answer Key| Ratio, Proportion, and Probability
1
1
Answer: 1 in 3 or 3 or 333 %
(1 point)
38. You toss a coin or spin a spinner
dependent
independent
Answer: independent
(1 point)
39. You draw a card, replace it, and then draw another card.
dependent
independent
Answer: independent
(1 point)
40. The hair in a typical man's beard grows about 3.5mm per week. Find the unit rate in mm per day.
Answer: 0.5 mm per day
Your Score
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