Problem-Solving and Data Analysis: Percentages — Quiz 4

Questions in this quiz (10)

1. The line graph shows the total amount of snow, in inches, recorded each year in Washington, DC, from $$2003$$ to $$2015$$. If $$p\%$$ is the percent decrease in the annual snowfall from $$2003$$ to $$2007$$, what is the value of $$p$$?

   • 75

2. In $$2015$$, a company's revenue increased by $$12\%$$, and in $$2016$$ it increased by another $$10\%$$. If the $$2016$$ revenue is $$k$$ times the $$2014$$ revenue, what is the value of $$k$$?

   • $$1.10$$
   • $$1.12$$
   • $$1.20$$
   • $$1.23$$

3. A store marks up an item by $$150\%$$ of its cost, then offers a discount of $$20\%$$ on the marked price. If the original cost was $$40$$ dollars, what is the final sale price?

   • $$64$$
   • $$72$$
   • $$80$$
   • $$96$$

4. A number increases by $$30\%$$, then decreases by $$20\%$$. What is the overall percent change?

   • $$4\%\ decrease$$
   • $$4\%\ increase$$
   • $$10\%\ increase$$
   • $$10\%\ decrease$$

5. A scientist observes that a chemical concentration increases by $$25\%$$ each hour. If the initial concentration is $$80$$ units, what is the concentration after $$2$$ hours?

   • $$100$$
   • $$120$$
   • $$125$$
   • $$156.25$$

6. A product's price is increased by $$x\%$$, then increased again by $$y\%$$. Which expression represents the final price in terms of the original price $$P$$?

   • $$P(1+x+y)$$
   • $$P(1+x)(1+y)$$
   • $$P(1+xy)$$
   • $$P\left(1+\frac{x}{100}\right)\left(1+\frac{y}{100}\right)$$

7. A tank is filled to $$60\%$$ of its capacity. After adding $$120$$ liters, the tank is $$90\%$$ full. What is the total capacity of the tank?

   • $$200$$
   • $$300$$
   • $$400$$
   • $$600$$

8. A population decreases by $$15\%$$ one year and then increases by $$20\%$$ the next year. What is the net percent change?

   • $$2\%\ decrease$$
   • $$2\%\ increase$$
   • $$5\%\ increase$$
   • $$5\%\ decrease$$

9. A store sells an item for $$78$$ dollars after applying a $$25\%$$ discount. What was the original price?

   • $$97.50$$
   • $$100$$
   • $$104$$
   • $$120$$

10. A number $$n$$ is increased by $$18\%$$ to become $$236$$. What is the value of $$n$$?

    • $$180$$
    • $$200$$
    • $$212$$
    • $$220$$