Quiz 1 - Percents

1. Compute 15% of 600.

 A) 9 B) 40 C) 90 D) 400 E) 900

2. 8 is what percent of 40?

 A) 5% B) 10% C) 15% D) 20% E) 25%

3. 5% of a number is 120. Find this number.

 A) 6 B) 24 C) 60 D) 600 E) 2400

4. We wish to increase quantity P by 20%. Which of the following is the correct expression?

 A) 20P B) 120P C) 0.2P D) 1.2P E) 2.2P

5. We wish to decrease quantity S by 8%. Which of the following is the correct expression?

 A) 1.08S B) 0.92S C) 1.8S D) 0.8S E) 0.2S

6. We increased the budget by 180%. Which of the following is true?

 A) The budget has almost doubled in size. B) The budget has almost tripled in size. C) There isn't enough information to say. D) The budget has increased 18 times in size. E) The budget has decreased to almost half of its previous amount.

7. We wish to increase quantity Q by 120%. Which of the following is the correct expression?

 A) 20Q B) 120Q C) 0.2Q D) 1.2Q E) 2.2Q

8. During the last year, the population of a town has increased by 30%. Today, there are 273,000 residents living in this town. How many residents were there a year ago?

 A) 210,000 B) 191,100 C) 81,900 D) 150,588 E) 35,490

9. In 2000, we purchased some stocks. By 2005, the stocks' value has increased by 20%. But then, during the next five years, it lost 20% of its value from 2005. How does the stocks' value in 2010 compare to the value in 2000?

 A) It is the same as in 2000. B) It is up by 4% compared to 2000. C) It is down by 4% compared to 2000. D) It is up compared to 2000 but we can't tell by how much. E) It is down compared to 2000 but we can't tell by how much.

10. Consider the same changes as in the problem above (i.e a 20% increase and a 20% decrease) but imagine that they happen in a reversed order: first we lose 20% of the price and then there is a 20% gain. How would the change in the order of these events affect the end result?

 A) The result would be the same as in the previous problem. B) The value of the stocks would be higher than in the previous problem. C) The value of the stocks would be lower than in the previous problem. D) It depends on how much the stocks were worth in 2000. E) It can not be determined.